Stability of Willingness to Pay: Does Time and Treatment Allocation in a Randomized Controlled Trial Influence Willingness to Pay?

BACKGROUND: Willingness-to-pay (WTP) estimates are useful to policy makers only if they are generalizable beyond the moment when they are collected. To understand the "shelf life" of preference estimates, preference stability needs be tested over substantial periods of time. METHODS: We tested the stability of WTP for preventative dental care (scale and polish) using a payment-card contingent valuation question administered to 909 randomized controlled trial participants at 4 time points: baseline (prerandomization) and at annual intervals for 3 years. Trial participants were regular attenders at National Health Service dental practices. Participants were randomly offered different frequencies (intensities) of scale polish (no scale and polish, 1 scale and polish per year, 2 scale and polishes per year). We also examined whether treatment allocation to these different treatment intensities influenced the stability of WTP. Interval regression methods were used to test for changes in WTP over time while controlling for changes in 2 determinants of WTP. Individual-level changes were also examined as well as the WTP function over time. RESULTS: We found that at the aggregate level, mean WTP values were stable over time. The results were similar by trial arm. Individuals allocated to the arm with the highest scale and polish intensity (2 per year) had a slight increase in WTP toward the latter part of the trial. There was considerable variation at the individual level. The WTP function was stable over time. CONCLUSIONS: The payment-card contingent valuation method can produce stable WTP values in health over time. Future research should explore the generalizability of these results in other populations, for less familiar health care services, and using alternative elicitation methods. HIGHLIGHTS: Stated preferences are commonly used to value health care.Willingness-to-pay (WTP) estimates are useful only if they have a "shelf life."Little is known about the stability of WTP for health care.We test the stability of WTP for dental care over 3 y.Our results show that the contingent valuation method can produce stable WTP values.

Text Messages With Financial Incentives for Men With Obesity: A Randomized Clinical Trial.

Importance: Effective weight loss interventions are needed for men with obesity. Objective: To determine whether an intervention that combined text messaging with financial incentives attained significant weight loss at the 12-month follow-up compared with the control group and whether an intervention of text messaging alone attained significant weight loss at the 12-month follow-up compared with the control group. Design, Setting, and Participants: An assessor-blinded randomized clinical trial conducted in Belfast, Bristol, and Glasgow areas in the UK. A total of 585 men with body mass index (BMI) of 30 or more were enrolled between July 2021 and May 2022. Final follow-up occurred June 2023. Interventions: Participants were randomly assigned to 12 months of behavioral focused text messages combined with financial incentives (n = 196), 12 months of behavioral focused text messages alone (n= 194), or a waiting list (control group; n= 195). The financial incentive consisted of a monetary reward that was lost if weight loss targets were not met. All participants received weight management information and a pedometer at baseline. Main Outcomes and Measures: The 2 primary comparisons were the 12-month comparison of within-participant weight change between the text messaging with financial incentive group and the control group and the comparison between the text messaging alone group and the control group (minimum clinically important difference, 3%). The P value defined for statistical significance was P < .025 for each comparison. Results: Of the 585 men (mean [SD] age, 50.7 [13.3] years; mean weight, 118.5 [19.9] kg; mean BMI, 37.7 [5.7]; 525 [90%] White), 227 (39%) lived in postal code areas with lower socioeconomic status, and 426 (73%) completed the 12-month follow-up. At the 12-month follow-up, compared with the control group, the mean percent weight change was significantly greater in the text messaging with financial incentive group (mean difference, -3.2%; 97.5% CI, -4.6% to -1.9%; P < .001) but was not significantly greater in the text messaging alone group (mean difference, -1.4%; 97.5% CI, -2.9% to 0.0, P = .05). The mean (SD) weight changes were -5.7 (7.4) kg for the text messaging with financial incentives group, -3.0 (7.5) kg for the text messaging alone group, and -1.5 (6.6) kg for the control group. The 12-month mean (SD) percentage weight changes from baseline were -4.8% (6.1%) for the text messaging with financial incentives group, -2.7% (6.3%) for text messaging alone group, and -1.3% (5.5%) for the control group. Of 366 adverse events reported, the most common were infections (83 [23%]). Of the 23 serious adverse events (6.3%), 12 (52%) occurred in the text messaging with financial incentives group, 5 (22%) in the texts messaging alone group, and 6 (26%) in the control group. None were considered related to participating in a trial group. Conclusion and Relevance: Among men with obesity, an intervention with text messaging with financial incentive significantly improved weight loss compared with a control group, whereas text messaging alone was not significantly better than the control condition. These findings support text messaging combined with financial incentives to attain weight loss in men with obesity. Trial Registration: isrctn.org Identifier: ISRCTN91974895.

UK general population's willingness to pay for dental check-ups.

OBJECTIVES: Choices about which dental treatments to provide in a publicly funded system should be guided by the value that the general population place on those treatments. The aim of this study was to estimate United Kingdom (UK) general population willingness to pay (WTP) for dental check-ups, and to investigate what factors influence WTP. METHODS: WTP was elicited using a hypothetical question in an online survey. The sample consisted of 594 participants, nationally representative of the UK general population in terms of age and gender. Regression analysis was used to examine what factors are associated with WTP. Analyses were conducted including and excluding protest answers. RESULTS: The mean WTP for a dental check-up is £31.32 for the full sample and £33.17 excluding protest answers. Respondents on higher incomes and those with higher university education had higher WTP. Respondents in Scotland were WTP less than respondents living in the rest of the UK which may be the result of NHS dental check-ups being free to patients in Scotland. CONCLUSION: The general UK population value dental check-ups. This study provides estimates of WTP for dental check-ups which can be used in Cost-Benefit Analyses.

The stability of physicians' risk attitudes across time and domains.

Risk attitude is known to influence physicians' decision-making under uncertainty. Research on the risk attitudes of physicians is therefore important in facilitating a better understanding of physicians' decisions. However, little is known about the stability of physicians' risk attitudes across domains. Using five waves of data from a prospective panel study of Australian physicians from 2013 to 2017, we explored the stability of risk attitudes over a four-year period and examined the association between negative life events and risk attitudes among 4417 physicians. Further, we tested the stability of risk attitude across three domains most relevant to a physician's career and clinical decision-making (financial, career and clinical). The results showed that risk attitude was stable over time at both the mean and individual levels but the correlation between domains was modest. There were no significant associations between negative life events and risk attitude changes in all three domains. These findings suggest that risk attitude can be assumed to be constant but domain-specificity needs to be considered in analyses of physician decision-making.

Doctor decision making with time inconsistent patients.

Non-adherence to treatments is prevalent. The aim of this paper is to model how doctors should adapt their medical treatment decisions if non-adherence is due to present-bias in the patient population, and to test the predictions of this model in a lab experiment. Under certain conditions, a rational doctor should adapt to non-adherence by choosing a treatment all patients complete (though less effective) when the probability of a patient being present-biased is sufficiently large. This is explored in a lab experiment where we test whether students in the doctor role adapt their behaviour as they learn about the distribution of non-adherence (due to present bias) in the patient population over the rounds of the experiment. We test the model prediction when we align individual incentives with the goal of maximising overall patient welfare. The results show that, on average, participants adapt to non-adherence as they learn about the probability of non-adherence (due to present-bias). However, a proportion of participants do not adapt to the optimal choice. The rate of adaptation was similar for the first 5 rounds under both individual incentives and salary. However, participants continued to adapt after round 5 under individual incentives whilst adaptation plateaued under salary. The adaptation to non-adherence may indicate that adherence can be improved by providing doctors with information about the probability of non-adherence (due to present-bias) in their patients.

Effectiveness and cost-effectiveness of text messages with or without endowment incentives for weight management in men with obesity (Game of Stones): study protocol for a randomised controlled trial.

BACKGROUND: Obesity increases the risk of type 2 diabetes, heart disease, stroke, mobility problems and some cancers, and its prevalence is rising. Men engage less than women in existing weight loss interventions. Game of Stones builds on a successful feasibility study and aims to find out if automated text messages with or without endowment incentives are effective and cost-effective for weight loss at 12 months compared to a waiting list comparator arm in men with obesity. METHODS: A 3-arm, parallel group, assessor-blind superiority randomised controlled trial with process evaluation will recruit 585 adult men with body mass index of 30 kg/m2 or more living in and around three UK centres (Belfast, Bristol, Glasgow), purposively targeting disadvantaged areas. Intervention groups: (i) automated, theory-informed text messages daily for 12 months plus endowment incentives linked to verified weight loss targets at 3, 6 and 12 months; (ii) the same text messages and weight loss assessment protocol; (iii) comparator group: 12 month waiting list, then text messages for 3 months. The primary outcome is percentage weight change at 12 months from baseline. Secondary outcomes at 12 months are as follows: quality of life, wellbeing, mental health, weight stigma, behaviours, satisfaction and confidence. Follow-up includes weight at 24 months. A health economic evaluation will measure cost-effectiveness over the trial and over modelled lifetime: including health service resource-use and quality-adjusted life years. The cost-utility analysis will report incremental cost per quality-adjusted life years gained. Participant and service provider perspectives will be explored via telephone interviews, and exploratory mixed methods process evaluation analyses will focus on mental health, multiple long-term conditions, health inequalities and implementation strategies. DISCUSSION: The trial will report whether text messages (with and without cash incentives) can help men to lose weight over 1 year and maintain this for another year compared to a comparator group; the costs and benefits to the health service; and men's experiences of the interventions. Process analyses with public involvement and service commissioner input will ensure that this open-source digital self-care intervention could be sustainable and scalable by a range of NHS or public services. TRIAL REGISTRATION: ISRCTN 91974895 . Registered on 14/04/2021.

Pulpotomy for the Management of Irreversible Pulpitis in Mature Teeth (PIP): a feasibility study.

BACKGROUND: Progression of dental caries can result in irreversible pulpal damage. Partial irreversible pulpitis is the initial stage of this damage, confined to the coronal pulp whilst the radicular pulp shows little or no sign of infection. Preserving the pulp with sustained vitality and developing minimally invasive biologically based therapies are key themes within contemporary clinical practice. However, root canal treatment involving complete removal of the pulp is often the only option (other than extraction) given to patients with irreversible pulpitis, with substantial NHS and patient incurred costs. The European Society of Endodontology's (ESE 2019) recent consensus statement recommends full pulpotomy, where the inflamed coronal pulp is removed with the goal of keeping the radicular pulp vital, as a more minimally invasive technique, potentially avoiding complex root canal treatment. Although this technique may be provided in secondary care, it has not been routinely implemented or evaluated in UK General Dental Practice. METHOD: This feasibility study aims to identify and assess in a primary care setting the training needs of general dental practitioners and clinical fidelity of the full pulpotomy intervention, estimate likely eligible patient pool and develop recruitment materials ahead of the main randomised controlled trial comparing the clinical and cost-effectiveness of full pulpotomy compared to root canal treatment in pre/molar teeth of adults 16 years and older showing signs indicative of irreversible pulpitis. The feasibility study will recruit and train 10 primary care dentists in the full pulpotomy technique. Dentists will recruit and provide full pulpotomy to 40 participants (four per practice) with indications of partial irreversible pulpitis. DISCUSSION: The Pulpotomy for the Management of Irreversible Pulpitis in Mature Teeth (PIP) study will address the lack of high-quality evidence in the treatment of irreversible pulpitis, to aid dental practitioners, patients and policymakers in their decision-making. The PIP feasibility study will inform the main study on the practicality of providing both training and provision of the full pulpotomy technique in general dental practice. TRIAL REGISTRATION: ISRCTN Registry, ISRCTN17973604 . Registered on 28 January 2021. Protocol version Protocol version: 1; date: 03.02.2021.

Psychological correlates of free colorectal cancer screening uptake in a Scottish sample: a cross-sectional observational study.

OBJECTIVES: Colorectal cancer (CRC) screening uptake in Scotland is 56%. This study examined whether psychological factors were associated with CRC screening uptake. DESIGN: Cross-sectional observational study. SETTING: This study used data from the Healthy AGeing In Scotland (HAGIS) pilot study, a study designed to be representative of Scottish adults aged 50 years and older. PARTICIPANTS: 908 (505 female) Scottish adults aged 50-80 years (mean age=65.85, SD=8.23), who took part in the HAGIS study (2016-2017). PRIMARY AND SECONDARY OUTCOME MEASURES: Self-reported participation in CRC screening was the outcome measure. Logistic regression was used to test whether scores on measures of health literacy, cognitive ability, risk aversion, time preference (eg, present oriented or future oriented) and personality were associated with CRC screening when these psychological factors were entered individually and simultaneously in the same model. RESULTS: Controlling for age, age-squared, sex, living arrangement, and sex*living arrangement, a one-point increase in risk aversion (OR=0.66, 95% CI 0.51 to 0.85) and present orientation (OR=0.86, 95% CI 0.80 to 0.94) was associated with reduced odds of screening. Higher scores on health literacy (OR per one-point increase=1.20, 95% CI 1.09 to 1.31), cognitive ability (OR per SD increase=1.51, 95% CI 1.25 to 1.81) and the intellect personality trait (OR per one-point increase=1.05, 95% CI 1.01 to 1.09) were associated with increased odds of screening. Higher risk aversion was the only psychological variable that was associated with CRC screening participation when all psychological variables were entered in the same model and remained associated with CRC screening when additionally adjusting for deprivation and education. A backward elimination model retained two psychological variables as correlates of CRC screening: risk aversion and cognitive ability. CONCLUSION: Individuals who are more risk averse are less likely to participate in free, home CRC screening.

UK general population willingness to pay for scale and polish, and detailed and personalized oral hygiene advice.

OBJECTIVES: Understanding the value the general population place on dentistry services is important for policymakers to aide service planning. Willingness to pay (WTP) is an economic method used to elicit the value of a good or service. The aim of this study is to estimate United Kingdom (UK) general population WTP for commonly provided scale and polish, and detailed and personalized oral hygiene advice (OHA), and to investigate what factors influence WTP. METHODS: Participants completed an online hypothetical WTP survey for scale and polish and detailed and personalized oral hygiene advice. The estimation sample consisted of 1405 participants, nationally representative of the UK general population in terms of age and sex. Regression analysis was used to estimate WTP and determine what factors are associated with WTP. Analyses were conducted including and excluding protest answers. RESULTS: The mean (SD) WTP for a scale and polish is £26.77 (£21.91) excluding protest answers and £24.80 (£22.71) for the full sample. The mean (SD) WTP for detailed and personalized OHA is £16.56 (£19.75) excluding protest answers and £12.77 (£22.28) for the full sample. Participants on higher incomes, private attenders and those who stated that maintaining clean and healthy gums was important had higher WTP for both services. Participants in Scotland and Northern Ireland were WTP less than their English counterparts, reflecting the different regional specific payment systems. CONCLUSION: The general UK population value scale and polish, and detailed and personalized OHA. This study provides estimates of WTP for these services which can be used to inform resource allocation decisions.

Selective Caries Removal in Permanent Teeth (SCRiPT) for the treatment of deep carious lesions: a randomised controlled clinical trial in primary care.

BACKGROUND: Dental caries is one of the most prevalent non-communicable disease globally and can have serious health sequelae impacting negatively on quality of life. In the UK most adults experience dental caries during their lifetime and the 2009 Adult Dental Health Survey reported that 85% of adults have at least one dental restoration. Conservative removal of tooth tissue for both primary and secondary caries reduces the risk of failure due to tooth-restoration, complex fracture as well as remaining tooth surfaces being less vulnerable to further caries. However, despite its prevalence there is no consensus on how much caries to remove prior to placing a restoration to achieve optimal outcomes. Evidence for selective compared to complete or near-complete caries removal suggests there may be benefits for selective removal in sustaining tooth vitality, therefore avoiding abscess formation and pain, so eliminating the need for more complex and costly treatment or eventual tooth loss. However, the evidence is of low scientific quality and mainly gleaned from studies in primary teeth. METHOD: This is a pragmatic, multi-centre, two-arm patient randomised controlled clinical trial including an internal pilot set in primary dental care in Scotland and England. Dental health professionals will recruit 623 participants over 12-years of age with deep carious lesions in their permanent posterior teeth. Participants will have a single tooth randomised to either the selective caries removal or complete caries removal treatment arm. Baseline measures and outcome data (during the 3-year follow-up period) will be assessed through clinical examination, patient questionnaires and NHS databases. A mixed-method process evaluation will complement the clinical and economic outcome evaluation and examine implementation, mechanisms of impact and context. The primary outcome at three years is sustained tooth vitality. The primary economic outcome is net benefit modelled over a lifetime horizon. Clinical secondary outcomes include pulp exposure, progession of caries, restoration failure; as well as patient-centred and economic outcomes. DISCUSSION: SCRiPT will provide evidence for the most clinically effective and cost-beneficial approach to managing deep carious lesions in permanent posterior teeth in primary care. This will support general dental practitioners, patients and policy makers in decision making. Trial Registration Trial registry: ISRCTN. TRIAL REGISTRATION NUMBER: ISRCTN76503940. Date of Registration: 30.10.2019. URL of trial registry record: https://www.isrctn.com/ISRCTN76503940?q=ISRCTN76503940%20&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search .

Examining the impact of oral hygiene advice and/or scale and polish on periodontal disease: the IQuaD cluster factorial randomised controlled trial.

Objective To compare the clinical effectiveness and cost benefit of different frequencies of scale and polish (S&P) treatments in combination with different types of oral hygiene advice (OHA).Design Multi-centre, multi-level cluster randomised factorial open trial with blinded outcome evaluation. UK dental practices were cluster randomised to deliver OHA as usual or personalised. In a separate randomisation, patients were allocated to receive S&P 6-monthly, 12-monthly or never.Setting UK primary dental care.Participants Practices providing NHS care and adults who had received regular dental check-ups.Main outcome measures The percent of sites with bleeding on probing, patient confidence in self-care, incremental net benefits (INB) over three years.Results Sixty-three practices and 1,877 adult patients were randomised and 1,327 analysed (clinical outcome). There was no statistically significant or clinically important difference in gingival bleeding between the three S&P groups (for example, six-monthly versus none: difference 0.87% sites, 95% CI: 1.6 to 3.3, p = 0.48) or between personalised or usual OHA groups (difference -2.5% sites, -95%CI: -8.3 to 3.3, p = 0.39), or oral hygiene self-efficacy (cognitive impact) between either group (for example, six-monthly versus none: difference -0.028, 95% CI -0.119 to 0.063, p = 0.543). The general population place a high value on, and are willing to pay for, S&P services. However, from a dental health perspective, none of the interventions were cost-effective.Conclusion Results suggest S&P treatments and delivering brief personalised OHA provide no clinical benefit and are therefore an inefficient approach to improving dental health (38% of sites were bleeding whatever intervention was received). However, the general population value both interventions.

Examining the effectiveness of different dental recall strategies on maintenance of optimum oral health: the INTERVAL dental recalls randomised controlled trial.

Objective To compare the clinical effectiveness of different frequencies of dental recall over a four-year period.Design A multi-centre, parallel-group, randomised controlled trial with blinded clinical outcome assessment. Participants were randomised to receive a dental check-up at six-monthly, 24-monthly or risk-based recall intervals. A two-strata trial design was used, with participants randomised within the 24-month stratum if the recruiting dentist considered them clinically suitable. Participants ineligible for 24-month recall were randomised to a risk-based or six-month recall interval.Setting UK primary dental care.Participants Practices providing NHS care and adults who had received regular dental check-ups.Main outcome measures The percentage of sites with gingival bleeding on probing, oral health-related quality of life (OHRQoL), cost-effectiveness.Results In total, 2,372 participants were recruited from 51 dental practices. Of those, 648 were eligible for the 24-month recall stratum and 1,724 participants were ineligible. There was no evidence of a significant difference in the mean percentage of sites with gingival bleeding on probing between intervention arms in any comparison. For those eligible for 24-month recall stratum: the 24-month versus six-month group had an adjusted mean difference of -0.91%, 95% CI (-5.02%, 3.20%); the 24-month group versus risk-based group had an adjusted mean difference of 0.07%, 95% CI (-3.99%, 4.12%). For the overall sample, the risk-based versus six-month adjusted mean difference was 0.78%, 95% CI (-1.17%, 2.72%). There was no evidence of a difference in OHRQoL (0-56 scale, higher score for poorer OHRQoL) between intervention arms in any comparison. For the overall sample, the risk-based versus six-month effect size was -0.35, 95% CI (-1.02, 0.32). There was no evidence of a clinically meaningful difference between the groups in any comparison in either eligibility stratum for any of the secondary clinical or patient-reported outcomes.Conclusion Over a four-year period, we found no evidence of a difference in oral health for participants allocated to a six-month or a risk-based recall interval, nor between a 24-month, six-month or risk-based recall interval for participants eligible for a 24-month recall. However, patients greatly value and are willing to pay for frequent dental check-ups.

Risk-based, 6-monthly and 24-monthly dental check-ups for adults: the INTERVAL three-arm RCT.

BACKGROUND: Traditionally, patients are encouraged to attend dental recall appointments at regular 6-month intervals, irrespective of their risk of developing dental disease. Stakeholders lack evidence of the relative effectiveness and cost-effectiveness of different recall strategies and the optimal recall interval for maintenance of oral health. OBJECTIVES: To test effectiveness and assess the cost-benefit of different dental recall intervals over a 4-year period. DESIGN: Multicentre, parallel-group, randomised controlled trial with blinded clinical outcome assessment at 4 years and a within-trial cost-benefit analysis. NHS and participant perspective costs were combined with benefits estimated from a general population discrete choice experiment. A two-stratum trial design was used, with participants randomised to the 24-month interval if the recruiting dentist considered them clinically suitable. Participants ineligible for 24-month recall were randomised to a risk-based or 6-month recall interval. SETTING: UK primary care dental practices. PARTICIPANTS: Adult, dentate, NHS patients who had visited their dentist in the previous 2 years. INTERVENTIONS: Participants were randomised to attend for a dental check-up at one of three dental recall intervals: 6-month, risk-based or 24-month recall. MAIN OUTCOMES: Clinical - gingival bleeding on probing; patient - oral health-related quality of life; economic - three analysis frameworks: (1) incremental cost per quality-adjusted life-year gained, (2) incremental net (societal) benefit and (3) incremental net (dental health) benefit. RESULTS: A total of 2372 participants were recruited from 51 dental practices; 648 participants were eligible for the 24-month recall stratum and 1724 participants were ineligible. There was no evidence of a significant difference in the mean percentage of sites with gingival bleeding between intervention arms in any comparison. For the eligible for 24-month recall stratum: the 24-month (n = 138) versus 6-month group (n = 135) had an adjusted mean difference of -0.91 (95% confidence interval -5.02 to 3.20); the risk-based (n = 143) versus 6-month group had an adjusted mean difference of -0.98 (95% confidence interval -5.05 to 3.09); the 24-month versus risk-based group had an adjusted mean difference of 0.07 (95% confidence interval -3.99 to 4.12). For the overall sample, the risk-based (n = 749) versus 6-month (n = 737) adjusted mean difference was 0.78 (95% confidence interval -1.17 to 2.72). There was no evidence of a difference in oral health-related quality of life between intervention arms in any comparison. For the economic evaluation, under framework 1 (cost per quality-adjusted life-year) the results were highly uncertain, and it was not possible to identify the optimal recall strategy. Under framework 2 (net societal benefit), 6-month recalls were the most efficient strategy with a probability of positive net benefit ranging from 78% to 100% across the eligible and combined strata, with findings driven by the high value placed on more frequent recall services in the discrete choice experiment. Under framework 3 (net dental health benefit), 24-month recalls were the most likely strategy to deliver positive net (dental health) benefit among those eligible for 24-month recall, with a probability of positive net benefit ranging from 65% to 99%. For the combined group, the optimal strategy was less clear. Risk-based recalls were more likely to be the most efficient recall strategy in scenarios where the costing perspective was widened to include participant-incurred costs, and in the Scottish subgroup. LIMITATIONS: Information regarding factors considered by dentists to inform the risk-based interval and the interaction with patients to determine risk and agree the interval were not collected. CONCLUSIONS: Over a 4-year period, we found no evidence of a difference in oral health for participants allocated to a 6-month or a risk-based recall interval, nor between a 24-month, 6-month or risk-based recall interval for participants eligible for a 24-month recall. However, people greatly value and are willing to pay for frequent dental check-ups; therefore, the most efficient recall strategy depends on the scope of the cost and benefit valuation that decision-makers wish to consider. FUTURE WORK: Assessment of the impact of risk assessment tools in informing risk-based interval decision-making and techniques for communicating a variable recall interval to patients. TRIAL REGISTRATION: Current Controlled Trials ISRCTN95933794. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme [project numbers 06/35/05 (Phase I) and 06/35/99 (Phase II)] and will be published in full in Health Technology Assessment; Vol. 24, No. 60. See the NIHR Journals Library website for further project information.

Traditionally, dentists have encouraged both patients at low risk and patients at high risk of developing dental disease to attend their dental practices for regular 6-month 'check-ups'. There is, however, little evidence available for either patients or dentists to use when deciding on the best dental recall interval (i.e. time between dental check-ups) for maintaining oral health. In this study, we wanted to find out, for adult patients who regularly attend the dentist, what interval of time between dental check-ups maintains optimum oral health and represents value for money. A total of 2372 adults who regularly attended 51 different dental practices across Scotland, Northern Ireland, England and Wales were involved. Patients aged 18 years or over who received all or part of their care as NHS patients were randomly allocated to groups to receive a check-up either every 6 months, at an individualised recall interval based on their own risk of oral disease (risk-based recall), or every 24 months (if considered at low risk by their dentist). The recruited adults completed questionnaires at their first trial appointment and then every year of the 4-year study. Their attendance at recall appointments was recorded and they received a clinical assessment taken by study staff at the end of their involvement at year 4. After 4 years, there was no evidence of a difference in the oral health of patients allocated to a 6-month or variable risk-based recall interval. For patients considered by their dentists to be suitable for a 24-month recall interval, there was no difference between those in the 24-month, 6-month or risk-based recall intervals. However, people greatly value and are willing to pay for frequent dental check-ups. The recall strategy that offers the best value for money to patients and the NHS, therefore, depends on what people and decision-makers wish to value within a health-care system.

Game of Stones: feasibility randomised controlled trial of how to engage men with obesity in text message and incentive interventions for weight loss.

OBJECTIVES: To examine the acceptability and feasibility of narrative text messages with or without financial incentives to support weight loss for men. DESIGN: Individually randomised three-arm feasibility trial with 12 months' follow-up. SETTING: Two sites in Scotland with high levels of disadvantage according to Scottish Index for Multiple Deprivation (SIMD). PARTICIPANTS: Men with obesity (n=105) recruited through community outreach and general practitioner registers. INTERVENTIONS: Participants randomised to: (A) narrative text messages plus financial incentive for 12 months (short message service (SMS)+I), (B) narrative text messages for 12 months (SMS only), or (C) waiting list control. OUTCOMES: Acceptability and feasibility of recruitment, retention, intervention components and trial procedures assessed by analysing quantitative and qualitative data at 3, 6 and 12 months. RESULTS: 105 men were recruited, 60% from more disadvantaged areas (SIMD quintiles 1 or 2). Retention at 12 months was 74%. Fewer SMS+I participants (64%) completed 12-month assessments compared with SMS only (79%) and control (83%). Narrative texts were acceptable to many men, but some reported negative reactions. No evidence emerged that level of disadvantage was related to acceptability of narrative texts. Eleven SMS+I participants (31%) successfully met or partially met weight loss targets. The cost of the incentive per participant was £81.94 (95% CI £34.59 to £129.30). Incentives were acceptable, but improving health was reported as the key motivator for weight loss. All groups lost weight (SMS+I: -2.51 kg (SD=4.94); SMS only: -1.29 kg (SD=5.03); control: -0.86 kg (SD=5.64) at 12 months). CONCLUSIONS: This three-arm weight management feasibility trial recruited and retained men from across the socioeconomic spectrum, with the majority from areas of disadvantage, was broadly acceptable to most participants and feasible to deliver. TRIAL REGISTRATION NUMBER: NCT03040518.

The migration of UK trained GPs to Australia: Does risk attitude matter?

BACKGROUND: Little is known about the drivers of migration of GPs. Risk attitude may play an important role as migration is fundamentally a risky decision that balances the risks of staying with the risks associated with leaving. This paper examines the association between risk attitudes and the migration of UK GPs to Australia. METHODS: GPs who qualified in the UK but work in Australia and who responded to the Medicine in Australia: Balancing Employment and Life (MABEL) national longitudinal survey of doctors, were compared with GPs based in Scotland who responded to a survey. Risk attitudes were elicited for financial risks, career and professional risks and clinical risks on a scale from 1 to 5. RESULTS: GPs in Scotland and UK trained GPs in Australia have similar risk attitudes for financial risk. However, UK trained GPs in Australia are less willing to take clinical and career risks. CONCLUSION: GPs who migrated to Australia after qualifying in the UK were more risk averse about their career and clinical risks. This may suggest that more risk averse GPs migrate to Australia due to pull factors such as less uncertainty around career and clinical outcomes in Australia. The uncertain NHS climate may push more risk averse doctors away from the UK.

The impact of quality and accessibility of primary care on emergency admissions for a range of chronic ambulatory care sensitive conditions (ACSCs) in Scotland: longitudinal analysis.

BACKGROUND: Hospital admissions for Ambulatory Care Sensitive Conditions (ACSC) are those that could potentially be prevented by timely and effective disease management within primary care. ACSC admissions are increasingly used as performance indicators. However, key questions remain about the validity of these measures. The evidence to date has been inconclusive and limited to specific conditions. The aim of this study was to test the robustness of ACSC admissions as indicators of the quality of primary care. It is the first study to examine a wide range of ACSCs using longitudinal data which enables us to control for unmeasured characteristics which differ by practice but which are constant over time. METHODS: Using longitudinal data at the practice level, from 907 Scottish practices for the time period 1/4/2005 to 31/32012, we explored the relationships between the quality of primary care, and hospital admissions for multiple ACSCs controlling for a wide range of covariates including characteristics of GP practices, characteristics of the practice population, hospital effects and year effects. We examined the impact of two dimensions of quality of care: clinical quality of and access to daytime general practice. Generalised Estimating Equations taking the form of Negative Binomial regression models with the practice population included as the exposure term were estimated. RESULTS: We found that higher achievement on some clinical quality measures of primary care was associated with reduced ACSC emergency admissions. We also show that access to primary care was associated with ACSC emergency admissions. However, the effects were small and inconsistent and ACSC emergency admissions were associated with several confounding factors such as deprivation, rurality and distance to the hospital. CONCLUSIONS: The results suggest caution in the use of crude ACSC admission rates as a performance indicator of quality of primary care.

A comparison of professional and private time preferences of General Practitioners.

In a perfect agency relationship, doctors consider all information and select the patient's 'utility maximising' option given the patient's preferences. The patient's time preferences are important as treatments vary in the timing and length of their benefits. However, doctors often do not have full information on patients' preferences and may apply their own preferences. This has generated empirical interest in estimating doctors' time preferences. However, these studies generally elicit doctors' private preferences (preferences for their own health) rather than professional preferences (preferences for the patient). We hypothesise that private and professional preferences may differ. Professional time preferences may be 'taught' in medical school or learned through repeated interactions with patients. If preferences differ then estimates of doctors' private preferences are less informative for medical decision-making. This study compares private and professional time preferences for health in a national sample of General Practitioners, using a between sample design. Time discounting is explored using exponential and quasi-hyperbolic models. We elicit time preferences using multiple price lists. We find no significant difference between the time preference for the self or the patient. This result holds for axiomatic discounting classification and maximum likelihood estimates. We do not find evidence of present-bias. There are a high proportion of increasingly impatient GPs, potentially implying a maximum 'willingness to wait' for treatment benefits. GPs value the health state differently between themselves or for a patient. These results suggest that we can use estimates of private preferences from doctors to inform medical decision-making.

Application of a discrete choice experiment approach to support the design of a hepatitis C testing service in primary care.

BACKGROUND: Ascertaining the acceptability of healthcare provision to service users is an important factor in promoting service uptake, especially for populations who are reluctant to access care. This study identified the attributes of a Hepatitis C (HCV) testing service for people prescribed Opioid Substitution Therapy (OST) and used their expressed preferences to guide design of a service, using an applied health economics approach. MATERIALS AND METHODS: Preferences of OST users were elicited using a discrete choice experiment. Important attributes for HCV testing were partly pre-determined by the research question and also identified using literature review and focus groups. Predetermined attributes included choice of provider and financial incentives. Other important attributes were place of testing; travel distance; attitudes and staff undertaking testing; waiting time for test results and incentive payment. The relative importance of defined attributes was assessed in 103 OST users attending 6 pharmacies from Dundee. RESULTS: OST users preferred testing at their "own pharmacy", by their drug worker, followed by their general practitioner (GP). Use of another pharmacy was the least preferred option. Being treated with dignity and respect was valued most highly, with waiting time for test results and travel distance also important. Financial incentives were not considered important. CONCLUSIONS: This study provides evidence that OST users prefer testing at their own pharmacy. The addition of a pharmacy to the providers offering HCV testing may increase uptake and support policies to eliminate HCV from our communities. Being treated with dignity and respect was highly valued and this suggests that testing uptake can be increased by developing positive relationships between OST users and test providers. Financial incentives were not found to be important.

INTERVAL (investigation of NICE technologies for enabling risk-variable-adjusted-length) dental recalls trial: a multicentre randomised controlled trial investigating the best dental recall interval for optimum, cost-effective maintenance of oral health in dentate adults attending dental primary care.

BACKGROUND: Traditionally, patients at low risk and high risk of developing dental disease have been encouraged to attend dental recall appointments at regular intervals of six months between appointments. The lack of evidence for the effect that different recall intervals between dental check-ups have on patient outcomes, provider workload and healthcare costs is causing considerable uncertainty for the profession and patients, despite the publication of the NICE Guideline on dental recall. The need for primary research has been highlighted in the Health Technology Assessment Group's systematic review of routine dental check-ups, which found little evidence to support or refute the practice of encouraging 6-monthly dental check-ups in adults. The more recent Cochrane review on recall interval concluded there was insufficient evidence to draw any conclusions regarding the potential beneficial or harmful effects of altering the recall interval between dental check-ups. There is therefore an urgent need to assess the relative effectiveness and cost-benefit of different dental recall intervals in a robust, sufficiently powered randomised control trial (RCT) in primary dental care. METHODS: This is a four year multi-centre, parallel-group, randomised controlled trial with blinded outcome assessment based in dental primary care in the UK. Practitioners will recruit 2372 dentate adult patients. Patient participants will be randomised to one of three groups: fixed-period six month recall, risk-based recall, or fixed-period twenty-four month recall. Outcome data will be assessed through clinical examination, patient questionnaires and NHS databases. The primary outcomes measure gingival inflammation/bleeding on probing and oral health-related quality of life. DISCUSSION: INTERVAL will provide evidence for the most clinically-effective and cost-beneficial recall interval for maintaining optimum oral health in dentate adults attending general dental practice. TRIAL REGISTRATION: ISRCTN95933794 (Date assigned 20/08/2008).