Gaby Judah

Experimental Pretesting of Hand-Washing Interventions in a Natural Setting

OBJECTIVES We pretested interventions derived from different domains of behavior change theory to determine their effectiveness at increasing hand washing with soap in a natural setting. METHODS We installed wireless devices in highway service station restrooms to record entry and soap use. Two text-only messages for each of 7 psychological domains were compared for their effect on soap-use rates. We collected data on nearly 200 000 restroom uses. RESULTS The knowledge activation domain was most effective for women, with a relative increase in soap use of 9.4% compared with the control condition (P = .001). For men, disgust was the most effective, increasing soap use by 9.8% (P = .001). Disgust was not significantly better than the control condition for women, nor was knowledge activation for men. Messages based on social norms and social status were effective for both genders. CONCLUSIONS Our data show that unobtrusive observation of behavior in a natural setting can help identify the most effective interventions for changing behaviors of public health importance. The gender differences we found suggest that public health interventions should target men and women differently.

The effect of handwashing with water or soap on bacterial contamination of hands.

Handwashing is thought to be effective for the prevention of transmission of diarrhoea pathogens. However it is not conclusive that handwashing with soap is more effective at reducing contamination with bacteria associated with diarrhoea than using water only. In this study 20 volunteers contaminated their hands deliberately by touching door handles and railings in public spaces. They were then allocated at random to (1) handwashing with water, (2) handwashing with non-antibacterial soap and (3) no handwashing. Each volunteer underwent this procedure 24 times, yielding 480 samples overall. Bacteria of potential faecal origin (mostly Enterococcus and Enterobacter spp.) were found after no handwashing in 44% of samples. Handwashing with water alone reduced the presence of bacteria to 23% (p < 0.001). Handwashing with plain soap and water reduced the presence of bacteria to 8% (comparison of both handwashing arms: p < 0.001). The effect did not appear to depend on the bacteria species. Handwashing with non-antibacterial soap and water is more effective for the removal of bacteria of potential faecal origin from hands than handwashing with water alone and should therefore be more useful for the prevention of transmission of diarrhoeal diseases.

Forming a flossing habit: An exploratory study of the psychological determinants of habit formation

OBJECTIVES Habit formation has been proposed as a means to promote maintenance of healthy behaviours, but there have been few investigations into how habits are formed. This exploratory study sought to model determinants of the formation of a dental flossing habit, including placement of the behaviour within the routine (before vs. after tooth-brushing), past behaviour, prospective memory ability, and motivational factors. DESIGN AND METHOD All participants (N = 50) received a motivational intervention designed to initiate behaviour change and habit formation. Half of the participants were instructed to floss before brushing, and half after. Participants subsequently self-reported flossing behaviour daily and, 4 weeks later, flossing automaticity. Automaticity and flossing frequency were also measured at 8-month follow-up. RESULTS Participants with stronger prospective memory ability, higher levels of past behaviour, and a more positive attitude flossed more frequently during the study. Stronger automaticity was predicted by positive attitudes, and increased behaviour frequency during and prior to the study. Those who flossed after brushing (rather than before) tended to form stronger flossing habits and, at 8-month follow-up, had stronger habits and flossed more frequently. CONCLUSIONS Habit forming interventions might usefully consider features of everyday routines and how behaviour may be reinforced. Suggestions for further research using more methodologically rigorous designs are offered. STATEMENT OF CONTRIBUTION What is already known on this subject? The formation of habit - that is, a learnt automatic response to contextual cues - requires initiation of a behaviour and repetition in a constant context. A recent formation study showed variation in habit strength despite equal repetitions, indicating that factors other than repetition may be important in habit development. From studies of routine behaviour, the boundaries between sub-routines are characterized by different processes than the middle of sub-routines, suggesting that placement of behaviour within existing routines may affect the likelihood of habit formation. What does this study add? Greater prospective memory ability predicted more frequent dental flossing. Initiating flossing after rather than before tooth-brushing promoted stronger habits. Positive attitudes impacted directly on habit formation, independent of behaviour repetition.

Dirty hands: bacteria of faecal origin on commuters' hands

Although many studies have investigated bacteria on the hands of health-care workers and caregivers, few have looked at microbiological contamination on the hands of the general adult public. This study investigated faecal bacteria on the hands of commuters in five UK cities. Of the 404 people sampled 28% were found to have bacteria of faecal origin on their hands. A breakdown by city showed that the proportion of people with contaminated hands increased the further north the city of investigation (P<0.001), an effect which was due in large part to a significant trend in men but not in women. Bus users were more contaminated than train users. The results of this exploratory study indicate that hand hygiene practices in the UK may be inadequate and that faecal indicator bacteria on hands may be used to monitor the effect of hand-washing promotion campaigns.

Sensor recorded changes in rates of hand washing with soap in response to the media reports of the H1N1 pandemic in Britain

Objectives To examine how the frequency of information regarding a real disease threat influences hand washing with soap. Design and setting The authors installed wireless devices in highway service station lavatories in England to record the proportion of individuals washing hands with soap from May 2009 to January 2010. Participants Participants were users of mens and womens toilets. Combined there was an average of 6800 participant entrances into the lavatories daily. Primary outcome measure The primary outcome measure is the proportion of soap usage to the number of entries into the lavatories. Results Hand-washing rates were positively related to both H1NI coverage in blogs and the news; however, these relationships were stronger for men than for women. Conclusions Hand washing with soap increases proportionally to the frequency of media key words related to H1N1. Womens hand washing was more strongly associated with incidence of media keywords than mens.

The development and validation of a Real Time Location System to reliably monitor everyday activities in natural contexts

Introduction The accurate measurement of behaviour is vitally important to many disciplines and practitioners of various kinds. While different methods have been used (such as observation, diaries, questionnaire), none are able to accurately monitor behaviour over the long term in the natural context of people’s own lives. The aim of this work was therefore to develop and test a reliable system for unobtrusively monitoring various behaviours of multiple individuals within the same household over a period of several months. Methods A commercial Real Time Location System was adapted to meet these requirements and subsequently validated in three households by monitoring various bathroom behaviours. Results The results indicate that the system is robust, can monitor behaviours over the long-term in different households and can reliably distinguish between individuals. Precision rates were high and consistent. Recall rates were less consistent across households and behaviours, although recall rates improved considerably with practice at set-up of the system. The achieved precision and recall rates were comparable to the rates observed in more controlled environments using more valid methods of ground truthing. Conclusion These initial findings indicate that the system is a valuable, flexible and robust system for monitoring behaviour in its natural environment that would allow new research questions to be addressed.

Financial disincentives? A three-armed randomised controlled trial of the effect of financial Incentives in Diabetic Eye Assessment by Screening (IDEAS) trial

Objective Conflicting evidence exists regarding the impact of financial incentives on encouraging attendance at medical screening appointments. The primary aim was to determine whether financial incentives increase attendance at diabetic eye screening in persistent non-attenders. Methods and analysis A three-armed randomised controlled trial was conducted in London in 2015. 1051 participants aged over 16 years, who had not attended eye screening appointments for 2 years or more, were randomised (1.4:1:1 randomisation ratio) to receive the usual invitation letter (control), an offer of £10 cash for attending screening (fixed incentive) or a 1 in 100 chance of winning £1000 (lottery incentive) if they attend. The primary outcome was the proportion of invitees attending screening, and a comparative analysis was performed to assess group differences. Pairwise comparisons of attendance rates were performed, using a conservative Bonferroni correction for independent comparisons. Results 34/435 (7.8%) of control, 17/312 (5.5%) of fixed incentive and 10/304 (3.3%) of lottery incentive groups attended. Participants who received any incentive were significantly less likely to attend their appointment compared with controls (risk ratio (RR)=0.56; 95% CI 0.34 to 0.92). Those in the probabilistic incentive group (RR=0.42; 95% CI 0.18 to 0.98), but not the fixed incentive group (RR=1.66; 95% CI 0.65 to 4.21), were significantly less likely to attend than those in the control group. Conclusion Financial incentives, particularly lottery-based incentives, attract fewer patients to diabetic eye screening than standard invites in this population. Financial incentives should not be used to promote screening unless tested in context, as they may negatively affect attendance rates.