Assessing Sample Bias among Venue-Based Respondents at Medical Marijuana Dispensaries

ABSTRACT

Venue-based sampling is the identification of, and outreach to, locations visited by the population of interest for the purpose of collecting data. The method is frequently used to reach specific populations, commonly referred to as “hidden populations.” Medical marijuana users represent a hidden population of persons who use marijuana for medicinal purposes. We examine whether venue-based procedures introduce selection or non-respondent bias into the study. The venue based sampling procedures employed for the UCLA Medical Marijuana Study used a two-stage, venue-based sampling approach. First, analyses were conducted to assess potential bias within dispensaries that agreed to participate in the surveys. Secondly, analyses were conducted to examine differences among patrons who responded to surveys. Overall, selection bias was generally absent among study results. Results also illuminated the minimal respondent bias observed among the survey respondents. Results suggest that the use of dispensaries to access and survey medical marijuana users is a viable option to gather patient information that adequately represents the greater population of medical marijuana users in Los Angeles. Thus, recommendations and conclusions based on findings from venue-based studies of medical marijuana users at dispensary sites serve to impartially inform meaningful research.     

Postal surveys — a view from the other side

Objectives — To explore the reasons why elderly people with arthritis choose to participate in a reliability study conducted by postal survey, and their views of the process of taking part. Methods — Twenty elderly people suffering from arthritis were interviewed in depth. They were chosen on the basis of how they had completed postal questionnaires about their arthritis, on two separate occasions to assess reliability, two weeks apart. Interviews were taped, with permission, and transcribed verbatim. Content analysis of the interview data, and any telephone calls, comments or letters received from all survey recipients, was conducted using NUD‐IST. Key findings — Many respondents thought that such surveys only involved the worst sufferers and that anyone else was “a fraud”. Part of the motivation for individuals to participate was the desire to help the researcher, others with arthritis or, for some respondents, themselves. The details of the questionnaires were used by the respondents as clues to develop their theories of the survey's purpose. There was commonly a failure to perceive the need to complete the questionnaires twice, regardless of whether there had been a change in their health. Some respondents did not see the point of the second questionnaires, some apologised for their unchanged health, and others actively sought to find further information to put into the second set. Conclusion — These results have implications for researchers, by identifying the range of detail required by potential survey respondents to reduce response bias. If the purpose of the survey is not clearly communicated, participants will impose their own, probably different, interpretation, with unexpected consequences.     

What is the price of perfection? The hidden costs of using detailed assessment instruments to measure alcohol consumption

OBJECTIVE: This article describes results from a study investigating the effects of using long assessment instruments on attrition rates in mailed-out surveys. METHOD: Participants were randomly assigned to receive one of two versions of a mailed-out survey; one version incorporated a detailed assessment of drinking using the Timeline Follow back method (TLFB; n = 46) and the other employed a brief graduated frequency measure of alcohol consumption (n = 49). RESULTS: 29% fewer respondents who received the TLFB returned any of their survey materials as compared to those respondents who received just the graduated frequency measure (22% vs 51%). CONCLUSIONS: In some situations, e.g., mailed-out surveys, employing detailed survey instruments may not be justified as the increased respondent burden may result in increased attrition rates.     

Planning the prevention of alcohol and other drug-related problems among women

The aim of this paper is to report on the findings from a survey of key respondents with regard to the prevention of alcohol and other drug problems among women. The findings suggest that key respondents were concerned about the problems related to legal substances, alcohol, nicotine, minor tranquillisers, over-the-counter medication and major psychotropic medication. The problems described by these respondents included both physical and psychological health problems. The implications of these findings for prevention activity are discussed.     

Optimistic bias and preventive behavioral engagement in the context of COVID-19

BackgroundThe coronavirus (COVID-19) pandemic presents a global crisis. To remain safe, individuals must take preventive measures. Health behavior theories suggest that perceived risk is a key determinant of engagement in preventive behavior. People often underestimate their risk for disease compared with similar others’, a phenomenon known as optimistic bias (OB).ObjectiveThis study aimed to explore how OB affected individuals' engagement in COVID-19 preventive behavior/intentions. Based on health behavior theories, this study considered risk perception and risk response as mediators of the relationship between OB and individuals’ preventive health behaviors and intentions.MethodsThis study used a cross-sectional survey design. Online survey platforms were used to recruit U.S. adults. A total of 293 valid responses were included in the analyses. Multivariate regression analyses were conducted to determine the relationship of OB to the respondents’ health information seeking intention and related behavioral outcomes.ResultsResults from the first regression model showed that OB was negatively related to risk perception. In other words, optimistically biased respondents perceived their risk of COVID-19 to be low. The second model demonstrated that perceived risk was related positively to affective responses to risk (e.g., worry and fear). That is, the lower their perceived risk of COVID-19, the less likely respondents were to feel anxiety and fear about this disease. Models 3 and 4 revealed positive relationships between risk response and respondents’ intentions and behaviors. Finally, the results supported a fully mediated pathway: OB → risk perception → risk response → information seeking intention and behavioral outcomes.ConclusionsThe study findings suggest that by decreasing their perceived risk and subsequent responses, optimistic bias can undermine individuals’ motivation to take precautions. To reduce this bias, the actual risk of COVID-19 should be reinforced.     

Nonresponse in a follow-up to a representative telephone survey of adult drinkers

OBJECTIVE: Examined predictors of nonresponse among respondents who agreed to receive a follow-up questionnaire on alcohol use after participating in a representative telephone survey, and among respondents who did and did not return the follow-up questionnaire. METHOD: A total of 2,072 (52.2% female) respondents to a representative monthly telephone survey were assessed on sociodemographic variables and alcohol use. Respondents were asked whether they would be willing to fill out an additional mailed questionnaire on alcohol use and attitudes toward drinking. Almost half (n = 956; 46%) of respondents agreed to participate in the follow-up survey; 430 (45%) of those individuals completed and returned the questionnaire. RESULTS: Agreement to receive the follow-up questionnaire was unrelated to alcohol use. Regarding gender, men were 1.42 times more likely than women to exhibit nonresponse in returning the follow-up questionnaire (95% CI: 1.08-1.42). After adjusting for the impact of demographic factors, respondents who consumed alcohol at least once per week were 1.43 times more likely than respondents who drank less frequently to exhibit nonresponse in returning the questionnaire (95% CI: 1.05-1.93). Respondents who consumed five or more standard drinks at least once per week were 1.83 times more likely to exhibit nonresponse in returning the questionnaire, compared with respondents who engaged in heavy drinking less frequently (95% CI: 1.15-2.92). CONCLUSIONS: Mailout questionnaires following a representative telephone survey may bias samples toward obtaining fewer men, fewer weekly drinkers and fewer heavier drinkers. Although the magnitude of these biases were relatively small, epidemiological studies on alcohol use may wish to oversample men and heavier drinkers in follow-up studies recruiting from population surveys.     

Alcohol,gender and partner aggression: a general population study of British adults

This study explored gender differences in the extent that alcohol affects the perceived severity of partner aggression, and assessed the relationship between partner aggression and drinking pattern. Respondents were asked questions related to their own drinking pattern and the most severe incident of physical aggression experienced by and to a spouse/romantic partner during the previous two years as part of a general population survey of 2027 adults in the UK conducted by interviewers using both oral and computer-assisted question format.

Approximately, 20% of respondents reported partner aggression, with drinking by one or both partners occurring in 35–40% of incidents. Alcohol use at the time of aggression was associated with increased severity of aggression, anger and fear, especially for aggression by a male toward a female respondent. Drinking patterns of the respondent and the partner predicted alcohol involvement in aggression, but not aggression that did not involve alcohol.     

Are differences in population prevalence of alcohol's harm to others related to survey administration mode?

Introduction and Aims. This study assessed the comparability of estimates of alcohol's harm to others across different administration modes in Swedish general population surveys. Harm was categorised as harm from strangers' drinking and harm from heavy drinkers known to the respondent. Design and Methods. Three surveys were conducted in 2011/2012 (n = 6841), including identical questions. One was based on self‐administered postal or Web questionnaires, and two were based on computer‐assisted telephone interviews of which one included a more ambitious procedure in terms of for example monetary incentives to the respondents. Pearson χ²‐tests were used to compare differences in the prevalence of harm. To estimate potential effects of survey mode, the samples were pooled, and multivariate Poisson regression models with mode as explanatory variable were used, adjusting for socio‐demographic and behavioural factors. Results. Respondents in the two computer‐assisted telephone interviews were more likely to report harm from strangers' drinking compared with respondents in the self‐administered postal or Web questionnaires. However, no significant differences were found between survey modes concerning reports of harm from known people's drinking. Discussion and Conclusions. A survey mode based on interviews seems to facilitate reports of harm from strangers' drinking. This does not apply to reports of harm from known people's drinking. Therefore, the comparability of estimates of alcohol's harm to others between survey modes depends on the type of harm being studied. [Sundin E, Landberg J, Galanti MR, Room R, Ramstedt M. Are differences in population prevalence of alcohol's harmto others related to survey administration mode?     

The impact of health education on the knowledge, attitudes and practices of a rural community with regards to schistosomiasis control using a plant molluscicide, Phytolacca dodecandra

OBJECTIVE: To determine the impact of health education on knowledge, attitudes and practices (KAP) with regards to use of a plant molluscicide in snail control. DESIGN: Repeat cross sectional survey. SETTING: Chiweshe communal lands. SUBJECTS: Males and females--age range 13 to 87 years. MAIN OUTCOME MEASURES: Changes in: KAP after health education, water usage pattern, water contact behaviour, willingness to participate in use of P. dodecandra. RESULTS: A high proportion of the community indicated prior knowledge of schistosomiasis during both knowledge, attitudes and practices (KAP) surveys. In the follow up KAP survey changes in the community's water contact behaviour as well as their practices in relation to sanitation were reported. The involvement of the community in the application of P. dodecandra during the course of the study ensured continued support and participation of the community. This was evidenced in the follow up survey when it was apparent that the community's attitude towards schistosomiasis had been influenced by the different activities that had taken place. CONCLUSION: Changes in the community's KAP with regards to schistosomiasis control, can be interpreted as an indication of the impact of the health education delivered during the course of the study. Health education should, therefore, precede programmes that require full participation of the community, as this enables the community to make informed decisions regarding their participation.     

Prospective student pharmacist interest in a rural pharmacy curriculum

Objective. To determine prospective student pharmacists' interest in a rural pharmacy health curriculum.Methods. All applicants who were selected to interview for fall 2011 enrollment at the UNC Eshelman School of Pharmacy were invited to participate in a Web-based survey. Questions addressed participants' willingness to participate in a rural health pharmacy curriculum, interest in practicing in a rural area, and beliefs regarding patient access to healthcare in rural areas.Results. Of the 250 prospective student pharmacists invited to participate, 91% completed the survey instrument. Respondents agreed that populations living in rural areas may have different health needs, and students were generally interested in a rural pharmacy health curriculum.Conclusions. An online survey of prospective student pharmacists was an effective way to assess their interest in a rural pharmacy program being considered by the study institution. Location of the rural program at a satellite campus and availability of housing were identified as factors that could limit enrollment.     

Psychedelic Drug (DPT)-Assisted Psychotherapy with Alcoholics: A Controlled Study

Abstract

The emergence of recovery as an organizing construct for behavioral health public policy and the resulting push to increase the recovery orientation of addiction treatment have sparked renewed questions about the prevalence of substance use disorder (SUD) remission/recovery within the general population. The present study reports findings on recovery-related questions imbedded within a public health survey conducted in Philadelphia and four adjacent counties in Southeastern Pennsylvania. The results reveal an adult recovery prevalence rate (9.4%) comparable to rates found in national surveys, but key measures of physical, emotional, and social health of adults in recovery suggest the need for assertive, sustained, and community-based approaches to recovery management that transcend brief episodes of professional intervention.     

Communities mobilizing for change on alcohol: outcomes from a randomized community trial

OBJECTIVE: Communities Mobilizing for Change on Alcohol (CMCA) was a randomized 15-community trial of a community organizing intervention designed to reduce the accessibility of alcoholic beverages to youths under the legal drinking age. METHOD: Data were collected at baseline before random assignment of communities to intervention or control condition, and again at follow-up after a 2.5-year intervention. Data collection included in-school surveys of twelfth graders, telephone surveys of 18- to 20-year-olds and alcohol merchants, and direct testing of the propensity of alcohol outlets to sell to young buyers. Analyses were based on mixed-model regression, used the community as the unit of assignment, took into account the nesting of individual respondents or alcohol outlets within each community, and controlled for relevant covariates. RESULTS: Results show that the CMCA intervention significantly and favorably affected both the behavior of 18- to 20-year-olds (effect size = 0.76, p<.01) and the practices of on-sale alcohol establishments (effect size = 1.18, p<.05), may have favorably affected the practices of off-sale alcohol establishments (effect size = 0.32, p = .08), but had little effect on younger adolescents. Alcohol merchants appear to have increased age-identification checking and reduced propensity to sell to minors. Eighteen- to 20-year-olds reduced their propensity to provide alcohol to other teens and were less likely to try to buy alcohol, drink in a bar or consume alcohol. CONCLUSIONS: Community organizing is a useful intervention approach for mobilizing communities for institutional and policy change to improve the health of the population.     

Reports of alcohol-related harm: telephone versus face-to-face interviews

OBJECTIVE: To assess the effect of mode of administration in alcohol surveys (telephone vs face-to-face interviews), prevalence rates of self-reported harms due to alcohol were compared for two datasets with equivalent measures. METHOD: Two national alcohol surveys were used: the 1990 Warning Labels Survey, in which random digit dialing was used to generate a sample of 2,000 adults interviewed by telephone, and the 1990 National Alcohol Survey (face-to-face interviews), a probability sample of U.S. adults living in households (N = 2,058). Both surveys included identical items on five areas of alcohol-related harm, yielding one composite index of any harm reported in the last 12 months that was compared between the two surveys for current drinkers. RESULTS: After controlling for demographic characteristics and alcohol use, the telephone survey yielded significantly higher rates of alcohol-related health harm, work harm and "any harm" as compared to the in-person survey. The interaction between heavier drinking (five or more drinks during 1 day, weekly or more often) and method of data collection was significant for health harm and any harm. Respondents in the telephone survey who drank 5+ less than weekly were more likely than those interviewed in person to report health harm due to alcohol use; those in the telephone survey who drank 5+ weekly or more often were more likely to report any harm. CONCLUSIONS: Possible explanations for differences between the surveys include anonymity and fewer social desirability issues associated with telephone surveys, as well as potentially differing cognitive requirements in telephone versus face-to-face interviews.     

Variations in self-reported health status: results from a New Zealand survey

AIMS: To report measures of the self-reported health of a sample of the New Zealand adult population elicited using the EuroQol Group's EQ-5D questionnaire, and to investigate variations in these measures, according to respondents' socio-demographic characteristics. METHODS: Personal health status questions were included in a self-completed postal questionnaire mailed to a non-stratified sample of 3000 New Zealanders, selected at random from the electoral roll. 1350 questionnaires were completed and returned. Each respondent rated their health on the five EQ-5D dimensions- mobility, self care, usual activities, pain/discomfort and anxiety/depression- and assigned a global score to their profile. RESULTS: Pain/discomfort was the most commonly experienced health problem, with 41% of all respondents and 63% of over-70 year olds reporting moderate or extreme problems. Just 4.5% of respondents reported problems with self-care. Respondents were more likely to report problems on each of the five dimensions and to have a lower global score if they smoked, if they were unemployed, a houseworker or retiree, and if their education did not continue past the minimum school leaving-age, or they did not have a degree or equivalent qualification. Problems on all dimensions were more common the older the respondent, and the global score was lower for over-70 year olds than for younger people. Neither the global score nor the incidence of problems on any of the dimensions was related to sex or ethnicity. CONCLUSIONS: The EQ-5D is a potentially useful instrument for monitoring health in the New Zealand context. Further research to explore its validity and reliability, particularly for Maori, would be valuable.     

Collecting substance use data with an anonymous mailed survey

Because mailed surveys minimize personal contact, they are useful for collecting sensitive data on substance use, as long as the problems of achieving adequate response rates can be conquered. To address these issues, we report on an anonymous mailed survey of substance use with a 78% response rate, including data collection and survey methods. Analysis of sociodemographic effects on responding found certain groups required additional contacts. Substance use estimates were not affected by non-response bias, suggesting that anonymous mailed surveys can be a feasible means of collecting data on substance use.