Strategies for maximizing consent rates for child dental health surveys: a randomised controlled trial.

BACKGROUND: Poor response rates can jeopardise the validity of the findings of epidemiological surveys. The aim of this study was to undertake a randomised controlled trial to determine the effectiveness of different strategies for maximizing parental consent rates for dental health surveys of young children. METHODS: The trial took place within the 2007/2008 NHS Epidemiological Dental Health Survey of 5-year-old children in the North West of England. Schools were randomised to one of five interventions: multiple letters to parents; promoting the research by providing additional information to parents and children; a financial incentive to the school; a financial incentive to the school administrator plus direct mailing to parents; and a control intervention comprising of usual practice, that is a single letter home to parents via the children. RESULTS: A total of 335 schools (11,088 children) were recruited. The mean percentage consent rates ranged from 47% (financial incentive to school administrator plus direct mailing) to 63% (multiple letters). Pair-wise comparisons indicated that the multiple letter group had a statistically significantly greater consent rate than the financial incentive to the school administrator plus direct mailing group and promoting the research by providing additional information group, but was not statistically significantly different from the financial incentive to the school group and the control group. CONCLUSIONS: There was little evidence to show that any of the five interventions made a significant difference to consent rates when compared to the control group. Financial incentives to schools were less effective than multiple reminder letters to parents. Trials should be built into surveys to test different interventions, in different contexts to expand the evidence base for improving consent rates in health surveillance programmes.

Patient perceptions regarding benefits of single visit scale and polish: a randomised controlled trial.

BACKGROUND: Single visit scale and polish is frequently carried out in dental practices however there is little evidence to support (or refute) its clinical effectiveness. The purpose of this research was to compare patient-reported outcomes between groups receiving a scale and polish at 6-, 12-, and 24-month intervals. Outcomes recorded included participants' subjective assessment of their oral cleanliness; the perceived importance of scale and polish for oral health and aesthetics; and frequency at which this treatment is required. METHODS: A practice-based randomised control trial was undertaken, with a 24-month follow-up period. Participants were healthy adults with no significant periodontal disease (BPE codes <3) randomly allocated to three groups to receive scale and polish at 6-, 12-, or 24-month intervals. Patient-reported outcomes were recorded at baseline and follow-up. Oral cleanliness was reported using a 5-point scale and recorded by examiners blinded to trial group allocation. A self-completed questionnaire enabled participants to report perceived importance of scale and polish (5-point scale), and required frequency of treatment (6-point scale). The main hypothesis was that participants receiving 6-monthly scale and polish would report higher levels of oral cleanliness compared to participants receiving scale and polish at 12- and 24-month intervals. RESULTS: 369 participants were randomised: 125 to the 6-month group; 122 to the 12-month group; and 122 to the 24-month group. Complete data set analysis was carried out to include 107 (6-month group), 100 (12-month group) and 100 (24-month group) participants. Multiple imputation analyses were conducted where follow-up data was missing. The difference in the proportions of participants reporting a 'high' level of oral cleanliness at follow-up was significant (Chi-squared P = 0.003): 52.3% (6-month group), 47.0% (12-month group) and 30.0% (24-month group). Scale and polish was thought to be important by the majority in each group for keeping mouths clean and gums healthy, whitening teeth, and preventing bad breath and tooth decay; there were no statistically significant differences between groups at follow-up. Most participants at follow-up thought that the frequency of scale and polish should be "every 6 months" or more frequently: 77.9% (6-month group), 64.6% (12-month group), 71.7% (24-month group); differences between groups were not statistically significant (Chi squared P = 0.126). The results suggest that participants in the 24-month trial group were more likely to choose a scale and polish interval of "once a year" or less frequently (OR 2.89; 95% CI 1.36, 6.13). CONCLUSIONS: The majority of healthy adults regarded 6-monthly single-visit scale and polish as being beneficial for their oral health. Receiving the treatment at different frequencies did not alter this belief; and those with the longest interval between scale and polish provision perceived that their mouth was less clean. In the absence of a strong evidence base to support (or refute) the effectiveness of single-visit scale and polish, the beliefs and preferences of patients regarding scale and polish may be influential drivers for maintaining provision of this treatment.

Clinical outcomes of single-visit oral prophylaxis: a practice-based randomised controlled trial.

BACKGROUND: Practice-based general dental practitioners routinely provide "scale and polish" or "oral prophylaxis" to patients attending their practices. Despite its routine provision, there is no evidence to support the clinical effectiveness of single-visit scale and polish, nor the frequency at which it should be provided. A recent systematic review recommended that future trials investigating scale and polish should involve dental practice patients. METHODS: A practice-based parallel randomised controlled trial with 24-month follow-up was conducted. Healthy adults (Basic Periodontal Examination [BPE] codes <3) were randomly assigned to 3 groups (6-month, 12-month, or 24-month interval between scale and polish). The primary outcome was gingival bleeding with the hypothesis that 6-monthly scale and polish would result in lower prevalence than 12-month or 24-month frequency. Follow-up measurements were recorded by examiners blinded to the allocation. 125, 122 and 122 participants were randomised to the 6-month, 12-month and 24-month groups respectively. Complete data set analyses were conducted for 307 participants: 107, 100, and 100 in the 6-month, 12-month and 24-month groups respectively. Chi-square test and ANOVA were used to compare treatment groups at follow-up. Logistic regression and ANCOVA were used to estimate the relationship between outcome and treatment group, adjusted for baseline values. Multiple imputation analyses were also carried out for participants with incomplete data sets. RESULTS: Prevalence of gingival bleeding at follow-up was 78.5% (6-month), 78% (12-month) and 82% (24-month) (p = 0.746). There were no statistically significant differences between groups with respect to follow-up prevalence of plaque and calculus. Statistically significant differences detected in the amount (millimetres) of calculus were too small to be clinically significant. Seventeen (4.6%) participants were withdrawn from the trial to receive additional treatment. CONCLUSIONS: This trial could not identify any differences in outcomes for single-visit scale and polish provided at 6, 12 and 24 month frequencies for healthy patients (with no significant periodontal disease). However, this is the first trial of scale and polish which has been conducted in a general practice setting and the results are not conclusive. Larger trials with more comprehensive measurement and long-term follow up need to be undertaken to provide a firm evidence base for this intervention. This trial informs the design of future practice-based trials on this subject.

Protocol for Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial: a randomised controlled trial to measure the effects and costs of a dental caries prevention regime for young children attending primary care dental services.

BACKGROUND: Dental caries is a persistent public health problem with little change in the prevalence in young children over the last 20 years. Once a child contracts the disease it has a significant impact on their quality of life. There is good evidence from Cochrane reviews including trials that fluoride varnish and regular use of fluoride toothpaste can prevent caries. The Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial will compare the costs and effects of a caries preventive package (fluoride varnish, toothpaste, toothbrush and standardised dental health education) with dental health education alone in young children. METHODS/DESIGN: A randomised controlled trial on children initially aged 2 and 3 years old who are regular attenders at the primary dental care services in Northern Ireland. Children will be recruited and randomised in dental practices. Children will be randomised to the prevention package of both fluoride varnish (twice per year for three years), fluoride toothpaste (1,450 ppm F) (supplied twice per year), a toothbrush (supplied twice a year) or not; both test and control groups receive standardised dental health education delivered by the dentist twice per year. Randomisation will be conducted by the Belfast Trust Clinical Research Support Centre ([CRSC] a Clinical Trials Unit). 1200 participants will be recruited from approximately 40 dental practices. Children will be examined for caries by independent dental examiners at baseline and will be excluded if they have caries. The independent dental examiners will examine the children again at 3 years blinded to study group.The primary end-point is whether the child develops caries (cavitation into dentine) or not over the three years. One secondary outcome is the number of carious surfaces in the primary dentition in children who experience caries. Other secondary outcomes are episodes of pain, extraction of primary teeth, other adverse events and costs which will be obtained from parental questionnaires. DISCUSSION: This is a pragmatic trial conducted in general dental practice. It tests a composite caries prevention intervention, which represents an evidence based approach advocated by current guidance from the English Department of Health which is feasible to deliver to all low risk (caries free) children in general dental practice. The trial will provide valuable information to policy makers and clinicians on the costs and effects of caries prevention delivered to young children in general dental practice. TRIAL REGISTRATION: EudraCT No: 2009 - 010725 - 39 ISRCTN: ISRCTN36180119 Ethics Reference No: 09/H1008/93:

A prospective study of dental anxiety in a cohort of children followed from 5 to 9 years of age.

BACKGROUND: The development of dental anxiety in children is poorly understood. AIMS: The aims of this study were to measure changes in dental anxiety over time and to examine the relationship between anxiety, dental care, and other factors. DESIGN: A prospective cohort study of children in the north-west of England followed from 5 to 9 years of age. The participants were clinically examined and their parents completed the same questionnaire at 5 and 9 years. RESULTS: The majority (54.3%N = 38) of participants who were anxious at 5 years were no longer anxious at 9 years, but a large proportion of children who were anxious at 5 remained anxious at 9 years of age (45.7%N = 32). During the follow-up period, a larger proportion of children developed anxiety (11.7%N = 85) than the proportion of children who were reported as being anxious at baseline (8.8%N = 70). At 9 years of age, dental anxiety was significantly associated with girls; parental anxiety; a history of extraction; and irregular, asymptomatic dental visiting. These factors were also significantly associated with dental anxiety at 5 years old. CONCLUSIONS: Dental anxiety was cumulative in the study population over time, and its development influenced by multiple variables. Results suggest that adverse conditioning and vicarious learning are both important in the development of this condition.

The geodemographic distribution of caries experience in neighboring fluoridated and nonfluoridated populations.

OBJECTIVE: This study compares the geodemographic distribution of caries experience in neighboring fluoridated and nonfluoridated populations. METHODS: All 5-year-old children living in fluoridated (N=1,422) and nonfluoridated (N=4,779) areas of Cheshire, UK, were examined by trained and calibrated examiners. The Target Market level of the Super Profiles geodemographic classification was used to produce market penetration ranking reports for caries experience. The same area types were compared in fluoridated and nonfluoridated populations. Lorenz curves and Gini coefficients were generated from the outputs of the penetration rankings. RESULTS: There was a 12.4 percent difference in prevalence and a 29.4 percent difference in dmft between fluoridated (dmft>0=32.4%, dmft=1.01) and nonfluoridated (dmft>0=37.0%, dmft=1.43) areas. The area types at the top of both penetration rankings were deprived in nature and those at the bottom were affluent. The Gini coefficients in each area were 22.7 and 23.7 percent. CONCLUSIONS: The results demonstrate that water fluoridation is effective at preventing dental disease after controlling for confounding factors. In both populations the majority of disease was not confined to a small number of deprived area types. This undermines the contention that a targeted approach to caries prevention is a practical option.

Comparing different methods to detect and correct nonresponse bias in postal questionnaire studies.

OBJECTIVES: This study compares methods for detecting and correcting the bias associated with nonresponse to postal questionnaires. METHODS: Questionnaires were sent out in three sequential stages to parents of all 5-year-old children examined in a clinical survey. Each stage progressively targeted nonresponders. Data on dmft and area measures of socioeconomic status were available for all children. Estimates for whole population dmft were produced by different methodologies comparing the relationship between dmft and stage of response and three area measures of socioeconomic status. RESULTS: A total of 1,776 children were examined and 1,437 questionnaires were obtained, a response rate of 80.9 percent. The mean dmft of the total population (1.49) was 17.3 percent more than responders (1.27). The dmft of the nonresponders was 2.41, 89.7 percent more than responders. There were significant linear trends in dmft and socioeconomic status across the mailing stages. The methodology using mailing stage regressed against dmft produced the most accurate adjusted dmft value (1.42). The methods using area measures of socioeconomic status produced nearly identical adjusted dmft values ranging from 1.31 to 1.32. CONCLUSIONS: Even with an "acceptable" response rate, nonresponse bias can still be present. Researchers should report the outcomes of analyses to detect nonresponse bias when publishing questionnaire studies.

Outcomes associated with restored and unrestored deciduous molar teeth.

INTRODUCTION: Most dental treatment for children in the United Kingdom (UK) is provided by general dental practitioners (GDPs) working in the National Health Service (NHS). A working party of the British Society of Paediatric Dentistry, in a special publication from the Dental Practice Board, has suggested that failure to provide restorative care for the deciduous dentition is unacceptable, yet GDPs are filling fewer teeth in young children. The study aimed to evaluate the health outcomes obtained from restoring carious deciduous molar teeth. METHOD: The dental records of 677 children cared for by 50 GDPs in the north west of England were analysed. RESULTS: The results showed that 18.8% of deciduous molars with unrestored caries and 17.0% with a history of restorative care went on to be extracted because of pain or sepsis. CONCLUSION: The results suggest that the risk of carious deciduous molars being extracted is similar whether these teeth receive restorative care or not.