Type of goals set and progress towards these goals, as part of a behaviour change intervention, in people with mild cognitive impairment: a secondary analysis.

BACKGROUND: Mild cognitive impairment (MCI) affects 5-20% of older people in the UK, but often goes undiagnosed and is associated with increased risk of dementia. Targeting risk factors such as physical inactivity and social isolation through behaviour-change interventions could reduce this risk. However, it is unclear how MCI impacts engagement with these interventions. We aimed to explore how MCI affects goal-setting priorities and progress towards these goals in a behaviour-change intervention (HomeHealth). METHODS: This was a secondary analysis of a completed randomised controlled trial, HomeHealth, which started in January 2021 and recruited 386 participants aged 65 years and older with mild frailty according to the Clinical Frailty Scale from general practices and the community in England. Participants were randomly assigned (1:1) to receive either the HomeHealth intervention (n=195) or treatment as usual (n=191) for 6 months. An evidence-based behaviour change intervention supported older people to work on goals to maintain independence, addressing factors affecting capability, opportunity, and motivation. Goal setting and progress information was available for 167 (86%) of 195 participants who received the intervention. The type of goal set and goal progress (scale 0-2) were compared between participants with healthy cognition, those with potential MCI, and those with probable dementia (rated with Montreal Cognitive Assessment [MoCA]). Qualitative semi-structured interviews were conducted between Aug 16, 2022, and May 18, 2023, with 29 people with MCI who received the intervention, to explore the perceived impact of MCI on goal setting, progress, and maintenance. Data were analysed using codebook thematic analysis. FINDINGS: The mean age of participants was 80·8 years, 105 (63%) of 167 were women and 158 (95%) were white. 54 (32%) of 167 participants had healthy cognition, 94 (56%) had potential MCI, and 19 (11%) probable dementia. Distribution of goal type was similar across the three groups, with most participants setting mobility goals. Progress towards goals (scale 0-2) was similar in people with healthy cognition and potential MCI (1·24 and 1·18, respectively) but lower in those with probable dementia (0·76). However, all met the moderate progress cutoff (0·66-1·32). People with MCI recognised their cognition was getting worse but did not feel the HomeHealth intervention could help. Rather than setting new goals, people with MCI built on existing behaviours. Many did not initially understand the intervention and felt they would have benefitted from contact in between sessions or from more sessions to help goal progress. Once the sessions ended, less than a quarter of participants maintained the goal progress. INTERPRETATION: Interventions to help older adults age well can be successfully delivered in people with MCI, to help them set and make progress towards goals. However, to maintain changes, more intense support is needed. FUNDING: National Institute for Health and Care Research (NIHR) School for Primary Care Research, NIHR Health Technology Assessment.

Goal setting as part of a holistic intervention to promote independence in older people with mild frailty: a process evaluation alongside a randomised controlled trial.

BACKGROUND: Frailty is a condition resulting from a decline in physiological reserves caused by an accumulation of several deficits, which progressively impairs the ability to recover from health adverse events. Following a promising feasibility study, the HomeHealth trial assessed a holistic tailored intervention for older adults with mild frailty to promote independence in their own homes, compared with usual care. We aimed to understand how goal setting worked among older people with mild frailty. METHODS: This study was a process evaluation alongside the HomeHealth randomised trial in older adults with mild frailty. The intervention was delivered at participants' homes, either in person or by telephone or videoconferencing. We carried out semi-structured interviews with older participants who had received the intervention (between three and six appointments), on average 233 days (range 68-465) after their last appointment, purposively sampled according to age, gender, number of sessions attended, adverse events, ethnicity, Index of Multiple Deprivation, Montreal Cognitive Assessment (MoCA) and Barthel scores, research site, and HomeHealth worker. We also conducted interviews with HomeHealth workers who delivered the intervention (n=7). Interviews explored the experience and process of goal setting, benefits and challenges, perceived progress, and behaviour change maintenance after the service had finished. Ethics approval was obtained, and all participants gave informed consent. Interviews were thematically analysed. HomeHealth workers kept formal records of goals set and assessed progress towards goals (0-2 rating scale) during six monthly-sessions, which were descriptively summarised. FINDINGS: 56 interviews were completed between July 15, 2022, and May 18, 2023. Study participants (n=49) had a mean age of 80 years (range 66-94), including 32 (65%) women and 17 (35%) men. Participants self-identified as White (n=42), Asian (n=3), Black (n=2), Mixed (n=1), and other ethnic (n=1) backgrounds. Findings suggested goal setting could be both a challenge and a motivator for older participants with mild frailty. Goal setting worked well when the older person could identify a clear need and set realistic goals linked to functioning, which led to a positive sense of achievement. Challenges occurred when older people were already accessing multiple resources and health services, or where the terminology of "goals" was off-putting due to work or school connotations. Average progress towards goals was 1·15/2. Most participants set goals around improving mobility (or a combination of mobility and another goal type such as socialising), and there was evidence of participants sustaining these behaviour changes after the intervention. INTERPRETATION: Older people with mild frailty can engage well with goal setting to promote independence. The lapse between receiving the intervention and being interviewed limited recall for some participants. However, the acceptability and adherence to the intervention for older people with mild frailty, and their moderate progress towards goals, should encourage further tailored and person-centred practices to promote their independence. FUNDING: National Institute for Health Research (NIHR) Health Technology Assessment.

Enabling health and maintaining independence for older people at home (HomeHealth trial): a multicentre randomised controlled trial.

BACKGROUND: NHS frailty services commonly target more severely frail older people, despite evidence suggesting frailty can be prevented or reversed when addressed at an earlier stage. HomeHealth is a new home-based, manualised voluntary sector service supporting older people with mild frailty to maintain their independence through behaviour change. Over six appointments, a trained HomeHealth worker discusses what matters to the older person and supports them to set and achieve goals around mobility, nutrition, socialising and/or psychological wellbeing. The service showed promising effects in a feasibility trial. We aimed to test the clinical and cost-effectiveness of HomeHealth for maintaining independence in older people with mild frailty compared with treatment as usual. METHODS: In this single-blind multicentre randomised controlled trial, we recruited community-dwelling older people aged 65 years or older with mild frailty from 27 general practices, community groups and sheltered housing in London, Yorkshire, and Hertfordshire. Participants were randomly assigned (1:1) to receive either HomeHealth monthly for 6 months or treatment as usual (usual GP and outpatient care, no specific frailty services). Our primary outcome was independence in activities of daily living, measured by blinded outcome assessors using the modified Barthel Index, and analysed using linear mixed models, including 6-month and 12-month data and controlling for baseline Barthel score and site. The study was approved by the Social Care Research Ethics Committee, and all participants provided written or orally recorded informed consent. This study is registered with the ISRCTN registry, ISRCTN54268283. FINDINGS: This trial took place between Jan 18, 2021, and July 4, 2023. We recruited 388 participants (mean age 81·4 years; 64% female [n=250], 94% White British/European [n=364], 2·5% Asian [n=10], 1·5% Black [n=6], 2·0% other [n=8]). We achieved high retention for 6-month follow-up (89%, 345/388), 12-month follow-up (86%, 334/388), and medical notes data (89%, 347/388). 182 (93%) of 195 participants in the intervention group completed the intervention, attending a mean of 5·6 appointments. HomeHealth had no effect on Barthel Index scores at 12 months (mean difference 0·250, 95% CI -0·932 to 1·432). At 6 months, there was a small reduction in psychological distress (-1·237, -2·127 to -0·348) and frailty (-0·124, -0·232 to -0·017), and at 12 months, we found small positive effects on wellbeing (1·449, 0·124 to 2·775) in those receiving HomeHealth. Other outcomes in analysis to date showed no significant difference. Health economic outcomes (including quality of life, capability, health services use and care needs or burden) are pending. INTERPRETATION: This high-quality trial showed that HomeHealth did not maintain independence in older people with mild frailty, and had limited effects upon secondary outcomes. Future studies need to explore different ways to promote health in this population. FUNDING: National Institute for Health and Care Research Health Technology Assessment (NIHR HTA).

The Specification of a Computational Model of Physical Activity Habit.

The influence of habit on physical activity is computationally modeled as the aggregated influence of past behavioral choices a person makes in a given context. We hypothesize that the influence of habit on behavior can be enhanced through engagement of the target behavior in a particular context or weakened through engagement of alternative behaviors in that context.

Breaking the Habit? Identifying Discrete Dimensions of Sitting Automaticity and Their Responsiveness to a Sitting-Reduction Intervention.

BACKGROUND: Growing evidence suggests that sitting is activated automatically on exposure to associated environments, yet no study has yet sought to identify in what ways sitting may be automatic. METHOD: This study used data from a 12-month sitting-reduction intervention trial to explore discrete dimensions of sitting automaticity, and how these dimensions may be affected by an intervention. One hundred ninety-four office workers reported sitting automaticity at baseline, and 3 months, 6 months, 9 months and 12 months after receiving one of two sitting-reduction intervention variants. RESULTS: Principal component analysis extracted two automaticity components, corresponding to a lack of awareness and a lack of control. Scores on both automaticity scales decreased over time post-intervention, indicating that sitting became more mindful, though lack of awareness scores were consistently higher than lack of control scores. CONCLUSION: Attempts to break office workers' sitting habits should seek to enhance conscious awareness of alternatives to sitting and afford office workers a greater sense of control over whether they sit or stand.

Challenging assumptions underlying physical activity promotion for health care professionals in Australia: A data-prompted interview study.

ISSUE ADDRESSED: Interventions targeting health care professionals' behaviours are assumed to support them in learning how to give behavioural advice to patients, but such assumptions are rarely examined. This study investigated whether key assumptions were held regarding the design and delivery of physical activity interventions among health care professionals in applied health care settings. This study was part of the 'Physical Activity Tailored intervention in Hospital Staff' randomised controlled trial of three variants of a web-based intervention. METHODS: We used data-prompted interviews to explore whether the interventions were delivered and operated as intended in health care professionals working in four hospitals in Western Australia (N = 25). Data were analysed using codebook thematic analysis. RESULTS: Five themes were constructed: (1) health care professionals' perceived role in changing patients' health behaviours; (2) work-related barriers to physical activity intervention adherence; (3) health care professionals' use of behaviour change techniques; (4) contamination between groups; and (5) perceptions of intervention tailoring. CONCLUSIONS: The intervention was not experienced by participants, nor did they implement the intervention guidance, in the way we expected. For example, not all health care professionals felt responsible for providing behaviour change advice, time and shift constraints were key barriers to intervention participation, and contamination effects were difficult to avoid. SO WHAT?: Our study challenges assumptions about how health care professionals respond to behaviour change advice and possible knock-on benefits for patients. Applying our learnings may improve the implementation of health promotion interventions in health care settings.

Development and validation of a questionnaire for assessing the determinants that predict household recycling (ReDom Questionnaire).

The growing tendency towards 'urbanization' is promoting an increase in resource consumption and waste generation, which requires proper waste separation management with active participation of the population. To this end, it is essential to know the personal modifiable factors that predict recycling. The primary aim of the present study is to develop and evaluate the psychometric properties of a Spanish language questionnaire designed to measure determinants of household waste separation for recycling purposes (ReDom Questionnaire). A cross-cultural adaptation, translation and psychometric evaluation was undertaken of an extant questionnaire originally developed in Swedish, and the resultant Spanish questionnaire was then subjected to reliability and validity testing. The questionnaire was developed using survey data from 759 respondents and 33 participants performed the retest to assess reliability. The resultant 'ReDom Questionnaire' is composed of three factors that draw on relevant elements of the COM-B framework: motivation (seven items), physical opportunity (three items) and social opportunity (three items). The accuracy of the scores is adequate both in terms of internal consistency (factorial weights >0.60; comparative fit index = 0.994; root mean square error of approximation = 0.049; root mean square residual (RMSR) = 0.053) and reliability (Pearson correlation >0.65; Cronbach's alpha >0.75). In conclusion, the Spanish ReDom Questionnaire showed adequate psychometric properties and appears useful for assessing the determinants of household waste separation.

Guided principal component analysis (GPCA): a simple method for improving detection of a known analyte.

There is increasing interest in the application of Raman spectroscopy in a medical setting, ranging from supporting real-time clinical decisions e.g. surgical margins to assisting pathologists with disease classification. However, there remain a number of barriers for adoption in the medical setting due to the increased complexity of probing highly heterogeneous, dynamic biological materials. This inherent challenge can also limit the deployment of higher level analytical approaches such as Artificial Intelligence (AI) including convolutional neural networks (CNN), as there is a lack of a ground truth required for training purposes i.e. in complex clinical samples. Principal component analysis (PCA) is an unsupervised data reduction approach (orthogonal linear transformation) that has been used extensively in spectroscopy for 30+ years, due to its capability to simplify analysis of complex spectroscopic data. However, due to PCA being unsupervised features will inherently appear mixed and their rank may vary between experiments. Here we propose Guided PCA (GPCA), a simple approach that allows PCA to be guided with spectral data to ensure a consistent rank of a key target moiety by the inclusion of a reference (guiding) spectrum to the data set. This simplifies analysis, increases robustness of PCA analysis and improves quantification and the limits of detection and decreases RMSE.

High wavenumber Raman spectroscopy for intraoperative assessment of breast tumour margins.

Optimal oncological results and patient outcomes are achieved in surgery for early breast cancer with breast conserving surgery (BCS) where this is appropriate. A limitation of BCS occurs when cancer is present at, or close, to the resection margin - termed a 'positive' margin - and re-excision is recommended to reduce recurrence rate. This is occurs in 17% of BCS in the UK and there is therefore a critical need for a way to assess margin status intraoperatively to ensure complete excision with adequate margins at the first operation. This study presents the potential of high wavenumber (HWN) Raman spectroscopy to address this. Freshly excised specimens from thirty patients undergoing surgery for breast cancer were measured using a surface Raman probe, and a multivariate classification model to predict normal versus tumour was developed from the data. This model achieved 77.1% sensitivity and 90.8% specificity following leave one patient out cross validation, with the defining features being differences in water content and lipid versus protein content. This demonstrates the feasibility of HWN Raman spectroscopy to facilitate future intraoperative margin assessment at specific locations. Clinical utility of the approach will require further research.

An intervention to promote positive homeworker health and wellbeing through effective home-working practices: a feasibility and acceptability study.

BACKGROUND: In the wake of Covid-19, the prevalence of working from home ('home-working') is expected to rise. Yet, working from home can have negative health and wellbeing impacts. Interventions are needed to promote effective ways of working that also protect workers' health and wellbeing. This study explored the feasibility and acceptability of an intervention intended to promote home-working practices that would protect and promote health behaviour and wellbeing. METHODS: An uncontrolled, single-arm mixed-methods trial design was employed. Forty-two normally-office-based UK workers, working from home between January-February 2021 (during the Covid pandemic), consented to receive the intervention. The intervention: a digital document offering evidence-based recommendations for home-working in ways conducive to health behaviour and wellbeing. Feasibility and acceptability were quantitatively indexed by: expressions of interest within 1 week (target threshold ≥ 35); attrition across the one-week study period (threshold ≤ 20%); and the absence of any apparent detriments in self-reported physical activity, sedentary behaviour, snacking, and work-related wellbeing prior to and one week after receiving the intervention. Qualitative think-aloud data, obtained while participants read through the intervention, and analysed using reflexive thematic analysis, explored acceptability. Semi-structured interviews conducted one week after intervention exposure were content-analysed to identify whether and which behaviour changes were adopted. RESULTS: Two feasibility criteria were met: 85 expressions of interest indicated satisfactory intervention demand, and no detriments were observed in health behaviours or wellbeing. Forty-two participants (i.e., maximum capacity for the study; 26 females, 16 males, aged 22-63) consented to take part. 31% dropped out over the one-week study period leaving a final sample of 29 (18 females, 11 males, aged 22-63), exceeding identified attrition thresholds. Think-aloud data showed that participants concurred with intervention guidance, but felt it lacked novelty and practicality. Follow-up interviews produced 18 (62%) participant reports of intervention adherence, where nine recommendations reportedly prompted behaviour change in at least one participant. CONCLUSIONS: Mixed evidence was found for intervention feasibility and acceptability. Whilst the information was deemed relevant and of value, further development is required to increase its novelty. It may also be more fruitful to provide this information via employers, to encourage and emphasise employer endorsement.

Experiences of initiating and maintaining a vegan diet among young adults: A qualitative study.

A vegan diet, which excludes all animal-derived products, has been associated with some improvements in health, while also conferring environmental benefits. Understanding the psychological determinants of successfully switching to a vegan diet will help to inform the design of interventions supporting long-term dietary change. Studies to date have tended to focus on reasoned motives underlying the decision to initiate such a dietary shift. Yet, focusing on reasons for switching may overlook the importance of a broader range of psychological factors that may help or hinder attempts to maintain a vegan diet. This qualitative interview study, the timing of which coincided with UK Covid-19 lockdowns, documented experiences of 20 young adults (17 female; mean age 22y) who attempted to adopt a vegan diet in the past nine months and had or had not successfully maintained this change. Reflexive Thematic Analysis identified five themes surrounding initiation and maintenance. A theme of 'motives, expectations and cues to switching' showed that switching was motivated by ethical or health concerns, and cued by Veganuary, lockdown or health issues. 'The effortfulness of switching' captured experiences of the perceived burden imposed by adhering to the diet due to, for example, a perceived lack of accessible vegan options. The 'flexibility of dietary rules' theme showed that many found the 'no animal products' rule clear but restrictive, so allowed themselves occasional non-meat animal products. 'Social acceptability concerns' captured the importance of acceptance from vegan and non-vegan family and friends, and 'satisfaction with the switch' described the perceived benefits that sustained maintenance for many. Our findings suggest that interventions should seek to support people to overcome potentially unforeseen practical and social challenges to adhering to a vegan diet.

Codevelopment of a Text Messaging Intervention to Support Adherence to Adjuvant Endocrine Therapy in Women With Breast Cancer: Mixed Methods Approach.

BACKGROUND: Adjuvant endocrine therapy (AET) reduces breast cancer recurrence and mortality in women with early-stage breast cancer. Unintentional nonadherence to AET is common (eg, forgetting to take medication). Forming habits surrounding medication taking could reduce reliance on memory and improve AET adherence. SMS text messaging interventions may offer a low-cost approach for promoting medication-taking habits. To optimize the likely effectiveness of such SMS text messages, the content should be developed using a transparent approach to ensure fidelity to relevant psychological theory and with user input to increase acceptability. OBJECTIVE: This study aimed to develop a pool of brief SMS text messages promoting habit formation to support AET adherence, which are acceptable to women with breast cancer and show fidelity to theory-based behavior change techniques (BCTs). METHODS: According to published literature, we selected 6 BCTs derived from the habit formation model: action planning, habit formation, restructuring the physical environment, adding objects to the environment, prompts/cues, and self-monitoring of behavior. In study 1, behavior change experts (n=10) created messages, each based on 1 of the 6 BCTs, in a web-based workshop and rated the fidelity of the messages to the intended BCT. In study 2, women with experience of taking AET discussed the acceptability of the messages in a focus group (n=5), and the messages were refined following this. In study 3, women with breast cancer rated the acceptability of each message in a web-based survey (n=60). In study 4, additional behavior change experts rated the fidelity of the remaining messages to the intended BCT in a web-based survey (n=12). Finally, a consultant pharmacist reviewed a selection of messages to ensure that they did not contradict general medical advice. RESULTS: In study 1, 189 messages were created targeting the 6 BCTs. In total, 92 messages were removed because they were repetitious, unsuitable, or >160 characters, and 3 were removed because of low fidelity (scoring <5.5/10 on a fidelity rating scale). Following study 2, we removed 13 messages considered unacceptable to our target population. In study 3, all remaining messages scored above the midpoint on an acceptability scale (1-5); therefore, no messages were removed (mean 3.9/5, SD 0.9). Following study 4, we removed 13 messages owing to low fidelity (scoring <5.5/10 on a fidelity rating scale). All the remaining messages showed fidelity to the intended BCTs (mean 7.9/10, SD 1.3). Following the pharmacist review, 2 messages were removed, and 3 were amended. CONCLUSIONS: We developed a pool of 66 brief SMS text messages targeting habit formation BCTs to support AET adherence. These showed acceptability to women with breast cancer and fidelity to the intended BCTs. The delivery of the messages will be further evaluated to assess their effect on medication adherence.

Clinical and cost-effectiveness of a personalised health promotion intervention enabling independence in older people with mild frailty ('HomeHealth') compared to treatment as usual: study protocol for a randomised controlled trial.

BACKGROUND: Frailty is clinically associated with multiple adverse outcomes, including reduced quality of life and functioning, falls, hospitalisations, moves to long-term care and mortality. Health services commonly focus on the frailest, with highest levels of need. However, evidence suggests that frailty is likely to be more reversible in people who are less frail. Evidence is emerging on what interventions may help prevent or reduce frailty, such as resistance exercises and multi-component interventions, but few interventions are based on behaviour change theory. There is little evidence of cost-effectiveness. Previously, we co-designed a new behaviour change health promotion intervention ("HomeHealth") to support people with mild frailty. HomeHealth is delivered by trained voluntary sector support workers over six months who support older people to work on self-identified goals to maintain their independence, such as strength and balance exercises, nutrition, mood and enhancing social engagement. The service was well received in our feasibility randomised controlled trial and showed promising effects upon outcomes. AIM: To test the clinical and cost-effectiveness of the HomeHealth intervention on maintaining independence in older people with mild frailty in comparison to treatment as usual (TAU). METHODS: Single-blind individually randomised controlled trial comparing the HomeHealth intervention to TAU. We will recruit 386 participants from general practices and the community across three English regions. Participants are included if they are community-dwelling, aged 65 + , with mild frailty according to the Clinical Frailty Scale. Participants will be randomised 1:1 to receive HomeHealth or TAU for 6 months. The primary outcome is independence in activities of daily living (modified Barthel Index) at 12 months. Secondary outcomes include instrumental activities of daily living, quality of life, frailty, wellbeing, psychological distress, loneliness, cognition, capability, falls, carer burden, service use, costs and mortality. Outcomes will be analysed using linear mixed models, controlling for baseline Barthel score and site. A health economic analysis and embedded mixed-methods process evaluation will be conducted. DISCUSSION: This trial will provide definitive evidence on the effectiveness and cost-effectiveness of a home-based, individualised intervention to maintain independence in older people with mild frailty in comparison to TAU, that could be implemented at scale if effective. TRIAL REGISTRATION: ISRCTN, ISRCTN54268283 . Registered 06/04/2020.

Supporting adjuvant endocrine therapy adherence in women with breast cancer: the development of a complex behavioural intervention using Intervention Mapping guided by the Multiphase Optimisation Strategy.

BACKGROUND: Adjuvant endocrine therapy (AET) reduces the risk of breast cancer recurrence and mortality. However, up to three-quarters of women with breast cancer do not take AET as prescribed. Existing interventions to support adherence to AET have largely been unsuccessful, and have not focused on the most salient barriers to adherence. This paper describes the process of developing four theory-based intervention components to support adherence to AET. Our aim is to provide an exemplar of intervention development using Intervention Mapping (IM) with guidance from the Multiphase Optimisation Strategy (MOST). METHODS: Iterative development followed the six-stage IM framework with stakeholder involvement. Stage 1 involved a literature review of barriers to adherence and existing interventions, which informed the intervention objectives outlined in Stage 2. Stage 3 identified relevant theoretical considerations and practical strategies for supporting adherence. Stage 4 used information from Stages 1-3 to develop the intervention components. Stages 1-4 informed a conceptual model for the intervention package. Stages 5 and 6 detailed implementation considerations and evaluation plans for the intervention package, respectively. RESULTS: The final intervention package comprised four individual intervention components: Short Message Service to encourage habitual behaviours surrounding medication taking; an information leaflet to target unhelpful beliefs about AET; remotely delivered Acceptance and Commitment Therapy-based guided self-help to reduce psychological distress; and a website to support self-management of AET side-effects. Considerations for implementation within the NHS, including cost, timing and mode of delivery were outlined, with explanation as to how using MOST can aid this. We detail our plans for the final stage of IM which involve feasibility testing. This involved planning an external exploratory pilot trial using a 24-1 fractional factorial design, and a process evaluation to assess acceptability and fidelity of intervention components. CONCLUSIONS: We have described a systematic and logical approach for developing a theoretically informed intervention package to support medication adherence in women with breast cancer using AET. Further research to optimise the intervention package, guided by MOST, has the potential to lead to more effective, efficient and scalable interventions.

Habit Facilitates Actioning Sun Protective Behavior Intentions.

Skin cancer is highly burdensome, but preventable with regular engagement in sun protective behaviors. Despite modest effectiveness of sun-protective behavior promotional efforts thus far, rates of engagement in sun-protective behaviors remain low. More is needed to understand motivation for using sunscreen, wearing sun-protective clothing, and seeking shade. This study tested whether the links of intention and habit strength with behavior differed between sun-protective behaviors. It was hypothesized that sun protective behaviors would be predicted by both habit and intention and that intention-behavior associations would be weaker for people with stronger habits. Participants residing in Queensland, Australia (N = 203; 75.96% female; M age = 37.16 years, SD = 14.67) self-reported their intentions and habit strength about sun-protective behavior for the next 7 days. Participants were followed-up 7 days later to self-report their sun-protective behavior. Multilevel modeling, accounting for nesting of multiple behaviors within-person, revealed that habit moderated the intention strength - behavior association and this moderation effect did not differ as a function of which behavior was being predicted. People with strong or moderate habit strength tended to act in line with their intentions; however, for people with very weak habits (2 SD < M), there was less alignment between their intention and behavior. These findings suggest that habit plays a facilitative role in the implementation of strong sun protective behavior intentions. Interventions should consider how to encourage intention and habit to enhance sun-protective behaviors and reduce the burden of skin cancer from sun exposure.Supplemental data for this article is available online at https://doi.org/10.1080/08964289.2021.1903380 .

Spatially Offset Raman Spectroscopy-How Deep?

Spatially offset Raman spectroscopy (SORS) is a technique for interrogating the subsurface composition of turbid samples noninvasively. This study generically addresses a fundamental question relevant to a wide range of SORS studies, which is how deep SORS probes for any specific spatial offset when analyzing a turbid sample or, in turn, what magnitude of spatial offset one should select to probe a specific depth. This issue is addressed by using Monte Carlo simulations, under the assumption of negligible absorption, which establishes that the key parameter governing the extent of the probed zone for a point-like illumination and point-like collection SORS geometry is the reduced scattering coefficient of the medium. This can either be deduced from literature data or directly estimated from a SORS measurement by evaluating the Raman intensity profile from multiple spatial offsets. Once this is known, the extent of the probed zone can be determined for any specific SORS spatial offset using the Monte Carlo simulation results presented here. The proposed method was tested using experimental data on stratified samples by analyzing the signal detected from a thin layer that was moved through a stack of layers using both non-absorbing and absorbing samples. The proposed simple methodology provides important additional information on SORS measurements with direct relevance to a wide range of SORS applications including biomedical, pharmaceutical, security, forensics, and cultural heritage.

Estimating the Reduced Scattering Coefficient of Turbid Media Using Spatially Offset Raman Spectroscopy.

We propose a new method for estimating the reduced scattering coefficient, µs', of turbid homogeneous samples using Spatially Offset Raman Spectroscopy (SORS). The concept is based around the variation of Raman signal with SORS spatial offset that is strongly µs'-dependent, as such, permitting the determination of µs'. The evaluation is carried out under the assumptions that absorption is negligible at the laser and Raman wavelengths and µs' is approximately the same for those two wavelengths. These conditions are often satisfied for samples analyzed in the NIR region of the spectrum where SORS is traditionally deployed. Through a calibration procedure on a PTFE model sample, it was possible to estimate the µs' coefficient of different turbid samples with an error (RMSEP) below 18%. The knowledge of µs' in the NIR range is highly valuable for facilitating accurate numerical simulations to optimize illumination and collection geometries in SORS, to derive in-depth information about the properties of SORS measurements or in other photon applications, dependent on photon propagation in turbid media with general impact across fields such as biomedical, pharmaceutical, security, forensic, and cultural sciences.

Self-absorption corrected non-invasive transmission Raman spectroscopy (of biological tissue).

The first near infrared window in biological tissue (λ∼ 700-950 nm) is of great interest for its potential to safely deliver light based diagnosis and therapeutic interventions, especially in the burgeoning field of nano-theranostics. In this context, Raman spectroscopy is increasingly being used to provide rapid non-invasive chemical molecular analysis, including bulk tissue analysis by exploiting the near infrared window, with transmission Raman spectroscopy (TRS). The disadvantage of this approach, is that when probing depths of several centimetres self-attenuation artefacts are typically exhibited, whereby TRS spectra can suffer from relative changes in the "spectral features" due to differential absorption of Raman photons by the various constituents of biological tissues. Simply put, for a homogenous substance with increasing thickness, spectral variances occur due to the optical properties of the material and not through changes in the chemical environment. This can lead to misinterpretation of data, or features of interest become obscured due to the unwanted variance. Here we demonstrate a method to correct TRS data for this effect, which estimates the pathlengths derived from peak attenuation and uses expected optical properties to transform the data. In a validation experiment, the method reduced total Raman spectral intensity variances >5 fold, and improved specific peak ratio distortions 35×. This is an important development for TRS, Spatially Offset Raman Spectroscopy (SORS) and related techniques operating at depth in the near IR window; applicable to samples where there is large sample thickness and inter- and intra-sample thickness is variable i.e. clinical specimens from surgical procedures such as breast cancer. This solution is expected to yield lower detection limits and larger depths in future applications such as non-invasive breast cancer diagnosis in vivo.

An experimental and numerical modelling investigation of the optical properties of Intralipid using deep Raman spectroscopy.

In this study, Monte Carlo simulations were created to investigate the distribution of Raman signals in tissue phantoms and to validate the arctk code that was used. The aim was to show our code is capable of replicating experimental results in order to use it to advise similar future studies and to predict the outcomes. The experiment performed to benchmark our code used large volume liquid tissue phantoms to simulate the scattering properties of human tissue. The scattering agent used was Intralipid (IL), of various concentrations, filling a small quartz tank. A thin sample of PTFE was made to act as a distinct layer in the tank; this was our Raman signal source. We studied experimentally, and then reproduced via simulations, the variation in Raman signal strength in a transmission geometry as a function of the optical properties of the scattering agent and the location of the Raman material in the volume. We have also found that a direct linear extrapolation of scattering coefficients between concentrations of Intralipid is an incorrect assumption at lower concentrations when determining the optical properties. By combining experimental and simulation results, we have calculated different estimates of these scattering coefficients. The results of this study give insight into light propagation and Raman transport in scattering media and show how the location of maximum Raman signal varies as the optical properties change. The success of arctk in reproducing observed experimental signal behaviour will allow us in future to inform the development of noninvasive cancer screening applications (such as breast and prostate cancers) in vivo.

Breaking habits or breaking habitual behaviours? Old habits as a neglected factor in weight loss maintenance.

Maintaining weight loss requires long-term behaviour change. Theory and evidence around habitual behaviour - i.e., action triggered by impulses that are automatically activated upon exposure to cues, due to learned cue-action associations - can aid development of interventions to support weight loss maintenance. Specifically, weight loss is more likely to be sustained where people develop new habits that support weight management, and break old habits that may undermine such efforts. Interventions seeking to break 'bad' weight-related habits have focused on inhibiting unwanted impulses or avoiding cues. This paper draws attention to the possibility that while such approaches may discontinue habitual behaviour, underlying habit associations may remain. We use evidence from existing qualitative studies to demonstrate that, left unchecked, unwanted habit associations can render people prone to lapsing into old patterns of unhealthy behaviours when motivation or willpower is momentarily weakened, or when returning to familiar settings following temporarily discontinued exposure. We highlight six behaviour change techniques especially suited to disrupting habit associations, but show that these techniques have been underused in weight loss maintenance interventions to date. We call for intervention developers and practitioners to adopt techniques conducive to forming new habit associations to directly override old habits, and to use the persistence of unwanted habit associations as a potential indicator of long-term weight loss intervention effectiveness.