Testing Behavioral Messages to Increase Recruitment to Health Research When Embedded Within Social Media Campaigns on Twitter: Web-Based Experimental Study.

BACKGROUND: Social media is rapidly becoming the primary source to disseminate invitations to the public to consider taking part in research studies. There is, however, little information on how the contents of the advertisement can be communicated to facilitate engagement and subsequently promote intentions to participate in research. OBJECTIVE: This paper describes an experimental study that tested different behavioral messages for recruiting study participants for a real-life observational case-control study. METHODS: We included 1060 women in a web-based experiment and randomized them to 1 of 3 experimental conditions: standard advertisement (n=360), patient endorsement advertisement (n=345), and social norms advertisement (n=355). After seeing 1 of the 3 advertisements, participants were asked to state (1) their intention to take part in the advertised case-control study, (2) the ease of understanding the message and study aims, and (3) their willingness to be redirected to the website of the case-control study after completing the survey. Individuals were further asked to suggest ways to improve the messages. Intentions were compared between groups using ordinal logistic regression, reported in percentages, adjusted odds ratio (aOR), and 95% CIs. RESULTS: Those who were in the patient endorsement and social norms-based advertisement groups had significantly lower intentions to take part in the advertised study compared with those in the standard advertisement group (aOR 0.73, 95% CI 0.55-0.97; P=.03 and aOR 0.69, 95% CI 0.52-0.92; P=.009, respectively). The patient endorsement advertisement was perceived to be more difficult to understand (aOR 0.65, 95% CI 0.48-0.87; P=.004) and to communicate the study aims less clearly (aOR 0.72, 95% CI 0.55-0.95; P=.01). While the patient endorsement advertisement had no impact on intention to visit the main study website, the social norms advertisement decreased willingness compared with the standard advertisement group (157/355, 44.2% vs 191/360, 53.1%; aOR 0.74, 95% CI 0.54-0.99; P=.02). The majority of participants (395/609, 64.8%) stated that the messages did not require changes, but some preferred clearer (75/609, 12.3%) and shorter (59/609, 9.7%) messages. CONCLUSIONS: The results of this study indicate that adding normative behavioral messages to simulated tweets decreased participant intention to take part in our web-based case-control study, as this made the tweet harder to understand. This suggests that simple messages should be used for participant recruitment through Twitter (subsequently rebranded X).

Understanding Public Attitudes and Willingness to Share Commercial Data for Health Research: Survey Study in the United Kingdom.

BACKGROUND: Health research using commercial data is increasing. The evidence on public acceptability and sociodemographic characteristics of individuals willing to share commercial data for health research is scarce. OBJECTIVE: This survey study investigates the willingness to share commercial data for health research in the United Kingdom with 3 different organizations (government, private, and academic institutions), 5 different data types (internet, shopping, wearable devices, smartphones, and social media), and 10 different invitation methods to recruit participants for research studies with a focus on sociodemographic characteristics and psychological predictors. METHODS: We conducted a web-based survey using quota sampling based on age distribution in the United Kingdom in July 2020 (N=1534). Chi-squared tests tested differences by sociodemographic characteristics, and adjusted ordered logistic regressions tested associations with trust, perceived importance of privacy, worry about data misuse and perceived risks, and perceived benefits of data sharing. The results are shown as percentages, adjusted odds ratios, and 95% CIs. RESULTS: Overall, 61.1% (937/1534) of participants were willing to share their data with the government and 61% (936/1534) of participants were willing to share their data with academic research institutions compared with 43.1% (661/1534) who were willing to share their data with private organizations. The willingness to share varied between specific types of data-51.8% (794/1534) for loyalty cards, 35.2% (540/1534) for internet search history, 32% (491/1534) for smartphone data, 31.8% (488/1534) for wearable device data, and 30.4% (467/1534) for social media data. Increasing age was consistently and negatively associated with all the outcomes. Trust was positively associated with willingness to share commercial data, whereas worry about data misuse and the perceived importance of privacy were negatively associated with willingness to share commercial data. The perceived risk of sharing data was positively associated with willingness to share when the participants considered all the specific data types but not with the organizations. The participants favored postal research invitations over digital research invitations. CONCLUSIONS: This UK-based survey study shows that willingness to share commercial data for health research varies; however, researchers should focus on effectively communicating their data practices to minimize concerns about data misuse and improve public trust in data science. The results of this study can be further used as a guide to consider methods to improve recruitment strategies in health-related research and to improve response rates and participant retention.

Testing temporal frames of colorectal cancer risks: evidence from randomized online experiments.

Low perceived risk of is associated with a low probability of engaging in risk preventive behaviours. Temporal framing has been suggested to make the risk seem higher, as narrower time frames appear to increase perceived risk and intentions to engage in risk-preventive behaviours. In two online experiments, we tested how manipulating risk information about colorectal cancer (CRC) influenced risk perception and preventive behaviours. 902 men and women aged 45-54 were recruited from an English online panel. Study 1 (N = 132) investigated how communicating CRC mortality instead of incidence rates influences risk perception, using both yearly and daily frames. In study 2 (N = 770), CRC incidence was described as occurring yearly, daily or hourly. The primary outcome measures were risk perception, intention to engage in preventive behaviours and whether participants chose to read information about ways to reduce CRC risk or skip it to finish the survey. Study 1 did not find a difference in intentions based on information about the risk of developing vs the risk of dying of CRC. Study 2 found that, while communicating CRC incidence occurring as every day increased information-seeking behaviour compared to every year and every hour (57.4% vs 45.9% vs 45.6%, p = 0.012), individuals in the daily condition were less likely to get all comprehension questions right (69.9% vs 78.2% vs 85.0%, respectively, p = 0.015). Temporal framing had no impact on perceived risk or intentions to engage in risk-reducing behaviours. While manipulating risk information in terms of temporal framing did not increase perceived risk, it may influence people's decision to engage with the information in the first place.

Effect of communicating community immunity on COVID-19 vaccine-hesitant people from ethnically diverse backgrounds: an experimental vignette study in the UK.

OBJECTIVES: Achieving high vaccination coverage is vital to the efforts of curbing the impact of the COVID-19 pandemic on public health and society. This study tested whether communicating the social benefit through community protection for friends and family members versus overall society, affects vaccination intention and perception among a sample enriched with respondents from black and ethnic minority backgrounds. DESIGN: A web-based experimental survey was conducted. Eligible participants were individually randomised, with equal probability, to one of the three experimental vignettes. SETTING: England. PARTICIPANTS: We recruited 512 (212 white, 300 ethnically diverse) vaccine-hesitant members from an online panel. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the intention to get vaccinated against COVID-19. The secondary outcome consisted of a behavioural measure in the form of active interest in reading more about the COVID-19 vaccine. Additional measures included the perceived importance and expected uptake in others, as well as the attitudes towards vaccination. RESULTS: Logistic regression models did not show an effect of the messages on intentions for the overall sample (society: adjusted OR (aOR): 128, 95% CI 0.88 to 1.88 and friends and family: aOR 1.32, 95% CI 0.89 to 1.94). The role of vaccination in achieving community immunity yielded higher vaccination intentions among study participants with white ethnic background (society: aOR: 1.94, 95% CI 1.07 to 3.51 and friends and family: aOR 2.07, 95% CI 1.08 to 3.96), but not among respondents from ethnically diverse backgrounds (society: aOR: 0.95, 95% CI 0.58 to 1.58 and friends and family: aOR 1.06, 95% CI 0.64 to 1.73). The messages, however, did not affect the perceived importance of the vaccine, expected vaccination uptake and active interest in reading more about the vaccine. CONCLUSIONS: Thus, although highlighting the social benefits of COVID-19 vaccinations can increase intentions among vaccine non-intenders, they are unlikely to address barriers among ethnically diverse communities.

Pneumococcal vaccination among adult risk patient with axial spondyloarthritis in Switzerland: Data from the survey of the ankylosing spondylitis association of Switzerland (SVMB).

While in Switzerland, pneumococcal vaccination is recommended for adult patients with axial spondyloarthritis (axSpA) treated with biological drugs, since 2014, little is known about the vaccination status of this specific patient population. This study assessed their vaccination status as part of a larger online survey by the ankylosing spondylitis association of Switzerland (SVMB). Out of 1560 who participated in the survey, 834 (53.5%) were eligible for the analysis. Vaccine coverage was low at 32.5% (271/834). Women and patients who got a flu shot every year were more likely to be covered. Age was negatively associated with being vaccinated. Most (54.2%; 147/271) were vaccinated by their general practitioner. Almost two-thirds of those who had not received the vaccine stated that it had not been offered to them (64.1%; 302/471). In summary, the vaccination coverage is low, but might be increased if the vaccine was offered systematically by general practitioners and specialists.

Testing the Effectiveness of an Animated Decision Aid to Improve Recruitment of Control Participants in a Case-Control Study: Web-Based Experiment.

BACKGROUND: Participation in case-control studies is crucial in epidemiological research. The self-sampling bias, low response rate, and poor recruitment of population representative controls are often reported as limitations of case-control studies with limited strategies to improve participation. With greater use of web-based methods in health research, there is a further need to understand the effectiveness of different tools to enhance informed decision-making and willingness to take part in research. OBJECTIVE: This study tests whether the inclusion of an animated decision aid in the recruitment page of a study website can increase participants' intentions to volunteer as controls. METHODS: A total of 1425 women were included in a web-based experiment and randomized to one of two experimental conditions: one in which they were exposed to a simulated website that included the animation (animation; n=693, 48.6%), and one in which they were exposed to the simulated website without the animation (control; n=732, 51.4%). The simulated website was adapted from a real website for a case-control study, which invites people to consider taking part in a study that investigates differences in purchasing behaviors between women with and without ovarian cancer and share their loyalty card data collected through 2 high street retailers with the researchers. After exposure to the experimental manipulation, participants were asked to state (1) their intention to take part in the case-control study, (2) whether they would be willing to share their loyalty card for research, and (3) their willingness to be redirected to the real website after completing the survey. Data were assessed using ordinal and binary logistic regression, reported in percentages (%), adjusted odds ratio (AOR), and 95% confidence intervals. RESULTS: Including the animation in the simulated website did not increase intentions to participate in the study (AOR 1.09; 95% CI 0.88-1.35) or willingness to visit the real study website after the survey (control 50.5% vs animation 52.6%, AOR 1.08; 95% CI 0.85-1.37). The animation, however, increased the participants' intentions to share the data from their loyalty cards for research in general (control 17.9% vs animation 26%; AOR 1.64; 95% CI 1.23-2.18). CONCLUSIONS: While the results of this study indicate that the animated decision aid did not lead to greater intention to take part in our web-based case-control study, they show that they can be effective in increasing people's willingness to share sensitive data for health research.

Evaluation of the Call for a Kit intervention to increase bowel cancer screening uptake in Lancashire, England.

OBJECTIVE: To evaluate the 'Call for a Kit' health promotion intervention that was initiated in Lancashire, England to improve bowel cancer screening uptake. METHODS: Within the intervention, screening non-responders are called and invited to attend a consultation with a health promotion team member at their primary care practice. In this audit, we analysed the proportion of those contacted who attended the in-person clinic versus those who received a phone consultation, the number returning a test kit from in-person versus phone consultations, and the extent to which test kit return was moderated by sociodemographic characteristics. RESULTS: In 2019, 68 practices participated in the intervention which led to 10,772 individuals being contacted; 2464 accepted the invitation to an in-person consultation, of whom 1943 attended. A further 1065 agreed to and attended a consultation over the phone. The 3008 consultations resulted in 2890 test kits being ordered, of which 1608 (55.6%) were returned. The intervention therefore yielded a 14.9% response rate in the total cohort; 71.5% of test kits came from individuals attending the in-person consultation. Women and those registered with a practice in socioeconomically deprived areas were less likely to return the test kit. Individuals with a black, mixed or a non-Indian/Pakistani Asian ethnic background were significantly more likely to accept the offer of an in-person consultation and return the test kit. CONCLUSION: Our analysis demonstrated the strong likelihood of people returning a test kit after an in-person appointment but also the usefulness of using phone consultations as a safety net for people unable or unwilling to attend in-person clinics.

Effectiveness of behavioural economics-based interventions to improve colorectal cancer screening participation: A rapid systematic review of randomised controlled trials.

•We searched PubMed, PsycInfo and EconLit for RCTs that evaluated BE interventions in CRC screening.•We identified 1027 papers for title and abstract review. 30 studies were eligible for the review.•The most frequently tested BE intervention was incentives, followed by default principle and salience.•Default-based interventions were most likely to be effective. Incentives had mixed evidence.•BE remains a promising field of interest in relation to influencing CRC screening behaviours.

Testing Enhanced Active Choice to Optimize Acceptance and Participation in a Population-Based Colorectal Cancer Screening Program in Malta.

Opt-out strategies have been shown to improve participation in cancer screening; however, there are ethical concerns regarding the presumed consent. In this study, we tested an alternative opt-in strategy, called: "enhanced active choice," in which the response options summarize the consequences of the decision. The study was conducted as part of the Maltese colorectal cancer screening program, which offers men and women, aged 60-64, a "one-off" fecal immunochemical test (FIT). A total of 8349 individuals were randomly assigned to receive either an invitation letter that featured a standard opt-in strategy (control condition), or an alternative letter with a modified opt-in strategy (enhanced active choice condition). Our primary outcome was participation three months after the invitation was delivered. Additionally, we also compared the proportion who said they wanted to take part in screening. We used multivariable logistic regression for the analysis. Overall, 48.4% (N = 4042) accepted the invitation and 42.4% (N = 3542) did the screening test. While there were no statistically significant differences between the two conditions in terms of acceptance and participation, enhanced active choice did increase acceptance among men by 4.6 percentage points, which translated to a significant increase in participation of 3.4 percentage points. We conclude that enhanced active choice can improve male screening participation. Given the higher risk of CRC in men, as well as their lower participation screening, we believe this to be an important finding.

Assessing the Effectiveness of Front of Pack Labels: Findings from an Online Randomised-Controlled Experiment in a Representative British Sample.

Front of pack food labels (FOPLs) provide accessible nutritional information to guide consumer choice. Using an online experiment with a large representative British sample, we aimed to examine whether FOPLs improve participants' ability to identify the healthiness of foods and drinks. The primary aim was to compare ability to rank between FOPL groups and a no label control. Adults (≥18 years), recruited from the NatCen panel, were randomised to one of five experimental groups (Multiple Traffic Light, MTL; Nutri-Score, N-S; Warning Label, WL; Positive Choice tick, PC; no label control). Stratification variables were year of recruitment to panel, sex, age, government office region, and household income. Packaging images were created for three versions, varying in healthiness, of six food and drink products (pizza, drinks, cakes, crisps, yoghurts, breakfast cereals). Participants were asked to rank the three product images in order of healthiness. Ranking was completed on a single occasion and comprised a baseline measure (with no FOPL), and a follow-up measure including the FOPL as per each participant's experimental group. The primary outcome was the ability to accurately rank product healthiness (all products ranked correctly vs. any incorrect). In 2020, 4504 participants had complete data and were included in the analysis. The probability of correct ranking at follow-up, and improving between baseline and follow-up, was significantly greater across all products for the N-S, MTL and WL groups, compared to control. This was seen for only some of the products for the PC group. The largest effects were seen for N-S, followed by MTL. These analyses were adjusted for stratification variables, ethnicity, education, household composition, food shopping responsibility, and current FOPL use. Exploratory analyses showed a tendency for participants with higher compared to lower education to rank products more accurately. Conclusions: All FOPLs were effective at improving participants' ability to correctly rank products according to healthiness in this large representative British sample, with the largest effects seen for N-S, followed by MTL.

Public preferences for using quantitative faecal immunochemical test versus colonoscopy as diagnostic test for colorectal cancer: evidence from an online survey.

BACKGROUND: There has been interest in using the non-invasive, home-based quantitative faecal immunochemical test (FIT) to rule out colorectal cancer (CRC) in high-risk symptomatic patients. AIM: To elicit public preferences for FIT versus colonoscopy (CC) and its delivery in primary care. DESIGN & SETTING: A cross-sectional online survey in England. METHOD: A total of 1057 adults (without CRC symptoms and diagnosis) aged 40-59 years were invited from an English online survey panel. Responders were asked to imagine they had been experiencing CRC symptoms that would qualify them for a diagnostic test. Participants were presented with choices between CC and FIT in ascending order of number of CRCs missed by FIT (from 1-10%). It was measured at what number of missed CRCs responders preferred CC over FIT. RESULTS: While 150 participants did not want either of the tests when both missed 1% CRCs, the majority (n = 741, 70.0%) preferred FIT to CC at that level of accuracy. However, this preference reduced to 427 (40.4%) when FIT missed one additional cancer. Women were more likely to tolerate missing CRC when using FIT. Having lower numeracy and perceiving a higher level of risk meant participants were less likely to tolerate a false negative test. Most of those who chose FIT preferred to return it by mail (62.2%), to be informed about normal test results by letter (42.1%), and about abnormal test results face to face (32.5%). CONCLUSION: While the majority of participants preferred FIT over CC when both tests had the same sensitivity, tolerance for missed CRCs was low.

Type 2 diabetes and colorectal cancer screening: Findings from the English Longitudinal Study of Ageing.

Objectives: Type 2 diabetes has been identified as a risk factor for colorectal cancer, but little is known about whether it influences participation in colorectal cancer screening programmes. This study tested the extent to which Type 2 diabetes is negatively associated with colorectal cancer screening uptake. Methods: We analysed individual data of screening eligible men and women aged 60­75 without cancer diagnosis from wave 6 of the English Longitudinal Study of Ageing (collected 2012­2013), to investigate whether Type 2 Diabetes influences colorectal cancer screening behaviour independently of demographic characteristics, body mass index, socio-economic status and other chronic diseases. Results: Individuals who reported to have Type 2 diabetes or had glycated haemoglobin (HbA1c) levels of 48 mmol/mol or higher were less likely to have ever completed a screening test (faecal occult blood test; 62.8% vs. 75.8%, p < 0.01) or to be up-to-date with their biennial screening invitation (60.2% vs. 72.0%, p < 0.05). The negative associations of Type 2 diabetes on colorectal cancer screening were found both in unadjusted and adjusted regression models. Conclusions: Future qualitative and quantitative research should identify reasons for this discrepancy, to inform interventions to increase screening uptake in this high-risk population.

Acceptability of risk-stratified breast screening: Effect of the order of presenting risk and benefit information.

Objective: To test whether reduced-frequency risk-stratified breast screening would be perceived more favourably by transposing the order of information on benefits and risks. Methods: After reading vignettes describing non-stratified three-yearly screening and a risk-stratified alternative with five-yearly invitations for women at low risk, 698 women completed an online survey. Participants were allocated at random to information on screening benefits followed by risks, or vice versa, and asked to state preferences for either screening system. Participants also rated perceived magnitude of screening benefits and risks, and breast cancer susceptibility. Results: Binomial logistic regression did not find order effects on preferences (p = 0.533) or perceived benefits of screening (p = 0.780). Perceived screening risks were greater when risks were presented first (p < 0.0005). Greater perceived susceptibility was associated with lower proportions preferring risk-stratified screening (15% vs. 39% in highest and lowest groups; p = 0.002), as were greater perceived screening benefits (e.g. 13% vs. 45% in highest and lowest groups; p < 0.0005). Conclusions: No information order effect on preferences was observed. Information order did affect screening risk perceptions. Efforts to improve perceptions may need to be more intensive than those tested. Women perceiving themselves as high risk or perceiving greater benefits of screening may be particularly averse to less frequent screening.

Predictors of intention translation in flexible sigmoidoscopy screening for colorectal cancer.

OBJECTIVE: This prospective study aimed to identify predictors of intention and subsequent attendance of flexible sigmoidoscopy screening using constructs derived from the Health Belief Model (HBM). METHOD: A total of 4,330 people aged 54 years and registered at 1 of 83 participating English general practices were sent a preinvitation questionnaire to assess sociodemographics, HBM variables including perceived benefits, barriers, seriousness, health motivation, and external cues to action as well a range of other constructs and personal characteristics known to relate to cancer screening. RESULTS: Of the 1,578 respondents (36.4%), 1,555 (98.5%) answered the intention question: 52.9% stated definitely yes, 38.1% probably yes, 6.8% probably not, and 2.2% definitely not. Intentions were positively associated with a higher score on a scale of benefits (odds ratio [OR] = 4.62; 95% confidence intervals [CI; 3.24, 6.59]) and health motivation, that is, interest in other ways of preventing colorectal cancer (OR = 2.61; 95% CI [1.62, 4.22]), while a higher score on perceived barriers (OR = 0.19; 95% CI [0.12, 0.31]) and currently following recommended healthy lifestyle behaviors (OR = 0.31; 95% CI [0.16, 0.59]) were negatively associated. Attendance was verified for 922 intenders (65.2%) of whom 737 (79.9%) attended. Attendance was predicted by health motivation (OR = 1.75; 95% CI [1.07, 2.86]), perceived benefits (OR = 1.82; 95% CI [1.37, 2.43]), perceived barriers (OR = 0.47; 95% CI [0.32, 0.69]), individual-level deprivation (OR = 0.26; 95% CI [0.14, 0.50]), and having diabetes (OR = 0.48; 95% CI [0.25, 0.94]). CONCLUSION: This study supported the usefulness of the HBM in predicting cancer screening and was further enhanced by adding non-HBM variables such as individual socioeconomic deprivation and comorbidities. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Testing verbal quantifiers for social norms messages in cancer screening: evidence from an online experiment.

BACKGROUND: Studies have shown that presenting correct information about group norms to correct misperceptions of norms can influence health behaviours. In two online studies we investigated how different ways of communicating the current uptake of 43% of the English Bowel Scope Screening (BSS) programme affects intention among disinclined men and women. METHODS: In the first study, 202 participants were asked to interpret eight quantifiers for 43% uptake ('few', 'many', 'a considerable number', 'a large number', 'a great number', 'a lot', 'numerous' and 'nearly half') and to indicate how misleading they perceived each of them to be. In the second study, with 1245 participants, we compared the motivational impact of two quantifiers ('a large number' and 'nearly half' which were associated with the highest perceived uptake (48.9%) and considered least misleading in study 1 respectively) with a control message that did not contain any information on uptake, and a message which communicated actual uptake as a proportion (43%). RESULTS: While we found that both verbal quantifiers increased screening intentions compared with the control group (from 7.8 to 12.5%, aOR 1.72; 95%CI 1.00-2.96 in the case of 'a large number' and 14.3%, aOR 2.02; 95%CI 1.20-3.38 for 'nearly half'), simply communicating that 43% do the test, however, had no impact on intentions (9.9% vs. 7.8% aOR 1.25; 95%CI 0.73-2.16). CONCLUSION: Verbal quantifiers can be used to improve the perception of low uptake figures and avoid a demotivating effect.

The impact of descriptive norms on motivation to participate in cancer screening - Evidence from online experiments.

OBJECTIVE: The current study tested in two online experiments whether manipulating normative beliefs about cancer screening uptake increases intention to attend colorectal screening among previously disinclined individuals. METHODS: 2461 men and women from an Internet panel (Experiment 1 N = 1032; Experiment 2, N = 1423) who initially stated that they did not intend to take up screening were asked to guess how many men and women they believe to get screened for colorectal cancer. Across participants, we varied the presence/absence of feedback on the participant's estimate, as well as the stated proportion of men and women doing the screening test. RESULTS: Across the two experiments, we found that receiving one of the experimental messages stating that uptake is higher than estimated significantly increased the proportion of disinclined men and women becoming intenders. While, we found a positive relationship between the communicated uptake and screening intentions, we did not find evidence that providing feedback on the estimate has an added benefit. CONCLUSION: Screening intention can be effectively manipulated through a high uptake message. PRACTICE IMPLICATIONS: Communication of high screening uptake is an easy and effective way to motivate disinclined individuals to engage in colorectal cancer screening.

Testing active choice for screening practitioner's gender in endoscopy among disinclined women: An online experiment.

OBJECTIVES: A large proportion of women have a preference for a same-gender endoscopy practitioner. We tested how information about practitioner gender affected intention to have bowel scope screening in a sample of women disinclined to have the test. METHODS: In an online experimental survey, women aged 35-54 living in England who did not intend to participate in bowel scope screening (N = 1060) were randomised to one of four experimental conditions: (1) control (practitioner's gender is unknown), (2) opposite-gender (male practitioner by default), (3) same gender (female practitioner by default), and (4) active choice (the patient could choose the gender of the practitioner). Intention was measured following the interventions. RESULTS: Of 1010 (95.3%) women who completed the survey, most were White-British (83.6%), and working (63.3%). Compared with control, both active choice and same-gender conditions increased intention among disinclined women (9.3% vs. 16.0% and 17.9%; OR: 1.85; 95% CI: 1.07-3.20 and OR: 2.07; 95% CI: 1.23-3.50). There were no differences in intention between the opposite-gender and control conditions (9.8% vs. 9.3%; OR: 1.06; 95% CI: 0.60-1.90) or the active choice and same-gender conditions (16.0% vs. 17.9%: OR: 0.89; 95% CI: 0.55-1.46, using same gender as baseline). CONCLUSIONS: Offering disinclined women a same-gender practitioner, either by choice or default, increased subsequent intention, while an opposite gender default did not negatively affect intention. Reducing uncertainty about gender of practitioner could positively affect uptake in women, and should be tested in a randomised controlled trial.