Assessing Mbiotisho: A smartphone application used to collect high-frequency health and nutrition data from difficult-to-reach populations.

There is an urgent need for improved and timely health and nutrition data. We developed and tested a smartphone application that caregivers from a pastoral population used to measure, record and submit high-frequency and longitudinal health and nutrition information on themselves and their children. The data were assessed by comparing caregiver-submitted measurements of mid-upper arm circumference (MUAC) to several benchmark data sets, including data collected by community health volunteers from the participating caregivers during the project period and data generated by interpreting photographs of MUAC measurements submitted by all participants. We found that the caregivers participated frequently and consistently over the 12-month period of the project; most of them made several measurements and submissions in at least 48 of the 52 weeks of the project. The evaluation of data quality was sensitive to which data set was used as the benchmark, but the results indicate that the errors in the caregivers' submissions were similar to that of enumerators in other studies. We then compare the costs of this alternative approach to data collection through more conventional methods, concluding that conventional methods can be more cost-effective for large socioeconomic surveys that value the breadth of the survey over the frequency of data, while the alternative we tested is favoured for those with objectives that are better met by high-frequency observations of a smaller number of well-defined outcomes.

A method of correction for heaping error in the variables using validation data.

When self-reported data are used in statistical analysis to estimate the mean and variance, as well as the regression parameters, the estimates tend, in many cases, to be biased. This is because interviewees have a tendency to heap their answers to certain values. The aim of the paper is to examine the bias-inducing effect of the heaping error in self-reported data, and study the effect on the heaping error on the mean and variance of a distribution as well as the regression parameters. As a result a new method is introduced to correct the effects of bias due to the heaping error using validation data. Using publicly available data and simulation studies, it can be shown that the newly developed method is practical and can easily be applied to correct the bias in the estimated mean and variance, as well as in the estimated regression parameters computed from self-reported data. Hence, using the method of correction presented in this paper allows researchers to draw accurate conclusions leading to the right decisions, e.g. regarding health care planning and delivery.

Validation of self-reported medication use applying untargeted mass spectrometry-based metabolomics techniques in the Rhineland study.

AIMS: To assess the validity of self-reported continuous medication use with drug metabolites measured in plasma by using untargeted mass spectrometric techniques. METHODS: In a population-based cohort in Bonn, Germany, we compared interview-based, self-reported medication intake with drug-specific metabolites measured in plasma (based on participants who completed their study visits between March 2016 and February 2020). Analyses were done stratified by sex and age (<65 years vs ≥65 years). Cohen's kappa (κ) statistics with 95% confidence intervals (CI) were calculated. RESULTS: A total of 13 drugs used to treat hypertension, gout, diabetes, epilepsy and depression were analysed in a sample of 4386 individuals (mean age 55 years, 56.1% women). Eleven drugs showed almost perfect agreement (κ > 0.8), whereas sitagliptin and hydrochlorothiazide showed substantial (κ = 0.8, 95% CI 0.71-0.90) and moderate agreement (κ = 0.61, 95% CI 0.56-0.66), respectively. Frequency of use allowed sex- and age-stratified analyses for eight and nine drugs, respectively. For five drugs, concordance tended to be higher for women than for men. For most drugs, concordance was higher among individuals aged ≥65 years than among individuals aged <65 years, but these age-related differences were not statistically significant. CONCLUSION: High concordance rates between self-reported drug use and metabolites measured in plasma suggest that self-reported drug use is reliable and accurate for assessing drug use.

Bias in self-reported parasite data from the salmon farming industry.

Many industries are required to monitor themselves in meeting regulatory policies intended to protect the environment. Self-reporting of environmental performance can place the cost of monitoring on companies rather than taxpayers, but there are obvious risks of bias, often addressed through external audits or inspections. Surprisingly, there have been relatively few empirical analyses of bias in industry self-reported data. Here, we test for bias in reporting of environmental compliance data using a unique data set from Canadian salmon farms, where companies monitor the number of parasitic sea lice on fish in open sea pens, in order to minimize impacts on wild fish in surrounding waters. We fit a hierarchical population-dynamics model to these sea-louse count data using a Bayesian approach. We found that the industry's monthly counts of two sea-louse species, Caligus clemensi and Lepeophtheirus salmonis, increased by a factor of 1.95 (95% credible interval: 1.57, 2.42) and 1.18 (1.06, 1.31), respectively, in months when counts were audited by the federal fisheries department. Consequently, industry sea-louse counts are less likely to trigger costly but mandated delousing treatments intended to avoid sea-louse epidemics in wild juvenile salmon. These results highlight the potential for combining external audits of industry self-reported data with analyses of their reporting to maintain compliance with regulations, achieve intended conservation goals, and build public confidence in the process.

Subjective cognitive complaints and permanent work disability: a prospective cohort study.

PURPOSE: Work disability (WD) is a medico-legal concept that refers to disability benefits (DB) granted due to diseases. We assessed whether subjective cognitive complaints (SCC)-presenting as self-rated difficulties of concentration, memory, clear thinking, and decision making-predict permanent WD in knowledge-intensive occupations. METHODS: In this prospective cohort study with up to 7-year follow-up, we combined the SCC questionnaire results with reliable registry data on the DBs of 7161 professional/managerial employees (46% females). We excluded employees who were on long-term sickness absence (SA) or had received a DB at baseline. The exposure variable was the presence of SCC. Age and SA before the questionnaire as a proxy measure of general health were treated as confounders and the analyses were conducted by gender. The outcome variable was a granted DB. The cumulative incidence function illustrates the difference between SCC categories, and the Fine-Gray model estimates the predictors of WD during the 8-year follow-up. RESULTS: The annual incidence of DB was 0.15% in the entire cohort: 0.18% among the females, and 0.12% among the males (p = 0.795). The most common primary reasons for permanent WD were mental (36%) and musculoskeletal (20%) disorders. SCC predicted DB in both genders when controlling for age and prior SA. Hazard ratios were 2.9 with a 95% confidence interval 1.4-6.0 for the females and 3.7 (1.8-7.9) for the males. CONCLUSION: Subjective cognitive complaints predict permanent WD in knowledge-intensive occupations. This finding has implications for supporting work ability and preventing work disability among employees with cognitively demanding tasks.

Anchoring biases affect repeated scores of thermal, moisture, tactile and comfort sensations in transient conditions.

In this study, we addressed potential biases which can occur when sensorial scores of temperature, wetness and discomfort are repeatedly reported, in transient exercise conditions. We pointed out that, when repeatedly reported, previous sensorial scores can be set by the participants as reference values and the subsequent score may be given based on the previous point of reference, the latter phenomenon leading to a bias which we defined as 'anchoring bias'. Indeed, the findings shown that subsequent sensorial scores are prone to anchoring biases and that the bias consisted in a systematically higher magnitude of sensation as compared to when reported a single time only. As such, the study allowed recognition, quantification and mitigation of the identified bias which can improve the methodological rigour of research studies involving assessments of sensorial data in transient conditions.

Intensified hand-hygiene campaign including soap-and-water wash may prevent acute infections in office workers, as shown by a recognized-exposure -adjusted analysis of a randomized trial.

BACKGROUND: Variable exposure to causative agents of acute respiratory (RTI) or gastrointestinal tract infections (GTI) is a significant confounding factor in the analysis of the efficacy of interventions concerning these infections. We had an exceptional opportunity to reanalyze a previously published dataset from a trial assessing the effect of enhanced hand hygiene on the occurrence of RTI or GTI in adults, after adjustment for reported exposure and other covariates. METHODS: Twenty-one working units (designated clusters) each including at least 50 office employees, totaling 1,270 persons, were randomized into two intervention arms (either using water-and-soap or alcohol-rub in hand cleansing), or in the control arm. Self-reported data was collected through weekly emails and included own symptoms of RTI or GTI, and exposures to other persons with similar symptoms. Differences in the weekly occurrences of RTI and GTI symptoms between the arms were analyzed using multilevel binary regression model with log link with personal and cluster specific random effects, self-reported exposure to homologous disease, randomization triplet, and seasonality as covariates in the Bayesian framework. RESULTS: Over the 16 months duration of the trial, 297 persons in the soap and water arm, 238 persons in the alcohol-based hand rub arm, and 230 controls sent reports. The arms were similar in age distribution and gender ratios. A temporally-associated reported exposure strongly increased the risk of both types of infection in all trial arms. Persons in the soap-and-water arm reported a significantly - about 24% lower weekly prevalence of GTI than the controls whether they had observed an exposure or not during the preceding week, while for RTI, this intervention reduced the prevalence only during weeks without a reported exposure. Alcohol-rub did not affect the symptom prevalence. CONCLUSIONS: We conclude that while frequent and careful hand washing with soap and water partially protected office-working adults from GTI, the effect on RTI was only marginal in this study. Potential reasons for this difference include partially different transmission routes and a difference in the virus load. In this trial, frequent standardized hand rubbing with ethanol-based disinfectant did not reduce the weekly prevalence of either type of infections. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00821509, 12 March 2009.

Measurement Reactivity in a Randomized Clinical Trial Using Self-Reported Data.

PURPOSE: The objective of this article is to describe how self-monitoring contributed to measurement reactivity in a randomized clinical trial (RCT). The implications of measurement reactivity on self-monitoring and suggestions for minimizing its effect will be discussed. DESIGN: The study involved a secondary data analysis of responses from 145 participants who completed a 12-month long RCT. The original sample consisted of 202 community-living adults with long-term indwelling urinary catheters. METHODS: The data analyzed were from the participants' brief responses to the final study question concerning their perceived study participation value. The data were discussed and coded iteratively until three researchers reached consensus. At the end, each item was recoded into eight categories and minor codes. FINDINGS: Our belief that the calendar was the probable cause of reactivity was not fully supported as the control group also learned about paying attention to urinary catheter problems by the questions asked through the seven bimonthly interviews. CONCLUSIONS: The calendar and interview questions were reactive by increasing participants' self-monitoring of catheter problems. Specifically, the frequent interviews exposed participants to catheter-related concerns and provided them with ideas as to how to better manage them. CLINICAL RELEVANCE: This article provides insight related to the internal validity threat of measurement reactivity in RCTs and gives suggestions to reduce its effects.

A cohort study examining emergency department visits and hospital admissions among people who use drugs in Ottawa, Canada.

BACKGROUND: The health of people who use drugs (PWUD) is characterized by multimorbidity and chronicity of health conditions, necessitating an understanding of their health care utilization. The objective of this study was to evaluate emergency department (ED) visits and hospital admissions among a cohort of PWUD. METHODS: We used a retrospective observational design between 2012 and 2013. The population was a marginalized cohort of PWUD (the PROUD study) for whom survey data was linked (n = 663) to provincial health administrative data housed at the Institute for Clinical Evaluative Sciences. We constructed a 5:1 comparison group matched by age, sex, income quintile, and region. The main outcomes were defined as having two or more ED visits, or one or more hospital admissions, in the year prior to survey completion. We used multivariable logistic regression analyses to identify factors associated with these outcomes. RESULTS: Compared to the matched cohort, PWUD had higher rates of ED visits (rate ratio [RR] 7.0; 95% confidence interval [95% CI] 6.5-7.6) and hospitalization (RR 7.7; 95% CI 5.9-10.0). After adjustment, factors predicting more ED visits were receiving disability (adjusted odds ratio [AOR] 3.0; 95% CI 1.7-5.5) or income assistance (AOR 2.7; 95% CI 1.5-5.0), injection drug use (AOR 2.1; 95% CI 1.3-3.4), incarceration within 12 months (AOR 1.6; 95% CI 1.1-2.4), mental health comorbidity (AOR 2.1; 95% CI 1.4-3.1), and a suicide attempt within 12 months (AOR 2.1; 95% CI 1.1-3.4). Receiving methadone (AOR 0.5; 95% CI 0.3-0.9) and having a regular family physician (AOR 0.5; 95% CI 0.2-0.9) were associated with lower odds of having more ED visits. Factors associated with more hospital admissions included Aboriginal identity (AOR 2.4; 95% CI 1.4-4.1), receiving disability (AOR 2.4; 95% CI 1.1-5.4), non-injection drug use (opioids and non-opioids) (AOR 2.2; 95% CI 1.1-4.4), comorbid HIV (AOR 2.4; 95% CI 1.2-5.6), mental health comorbidity (AOR 2.4; 95% CI 1.3-4.2), and unstable housing (AOR 1.9; 95% CI 1.0-3.4); there were no protective factors for hospitalization. CONCLUSIONS: Improved post-incarceration support, housing services, and access to integrated primary care services including opioid replacement therapy may be effective interventions to decrease acute care use among PWUD, including targeted approaches for people receiving social assistance or with mental health concerns.

Deviation between self-reported and measured occupational physical activity levels in office employees: effects of age and body composition.

OBJECTIVES: Whether occupational physical activity (PA) will be assessed via questionnaires or accelerometry depends on available resources. Although self-reported data collection seems feasible and inexpensive, obtained information could be biased by demographic determinants. Thus, we aimed at comparing self-reported and objectively measured occupational sitting, standing, and walking times adjusted for socio-demographic variables. METHODS: Thirty-eight office employees (eight males, 30 females, age 40.8 ± 11.4 years, BMI 23.9 ± 4.2 kg/m(2)) supplied with height-adjustable working desks were asked to report sitting, standing, and walking times using the Occupational Sitting and Physical Activity Questionnaire during one working week. The ActiGraph wGT3X-BT was used to objectively measure occupational PA during the same week. Subjectively and objectively measured data were compared computing the intra-class correlation coefficients, paired t tests and Bland-Altman plots. Furthermore, repeated-measurement ANOVAs for measurement (subjective vs. objective) and socio-demographic variables were calculated. RESULTS: Self-reported data yielded a significant underestimation of standing time (13.3 vs. 17.9%) and an overestimation of walking time (12.7 vs. 5.0%). Significant interaction effects of age and measurement of standing time (F = 6.0, p = .02, ηp(2) = .14) and BMI group and measurement of walking time were found (F = 3.7, p = .04, ηp(2) = .17). Older employees (>39 years) underestimated their standing time, while underweight workers (BMI < 20 kg/m(2)) overestimated their walking time. CONCLUSIONS: Self-reported PA data differ from objective data. Demographic variables (age, BMI) affect the amount of self-reported misjudging of PA. In order to improve the validity of self-reported data, a correction formula for the economic assessment of PA by subjective measures is needed, considering age and BMI.

Self-Report Tool for Identification of Individuals With Coronary Atherosclerosis: The Swedish CardioPulmonary BioImage Study.

BACKGROUND: Coronary atherosclerosis detected by imaging is a marker of elevated cardiovascular risk. However, imaging involves large resources and exposure to radiation. The aim was, therefore, to test whether nonimaging data, specifically data that can be self-reported, could be used to identify individuals with moderate to severe coronary atherosclerosis. METHODS AND RESULTS: We used data from the population-based SCAPIS (Swedish CardioPulmonary BioImage Study) in individuals with coronary computed tomography angiography (n=25 182) and coronary artery calcification score (n=28 701), aged 50 to 64 years without previous ischemic heart disease. We developed a risk prediction tool using variables that could be assessed from home (self-report tool). For comparison, we also developed a tool using variables from laboratory tests, physical examinations, and self-report (clinical tool) and evaluated both models using receiver operating characteristic curve analysis, external validation, and benchmarked against factors in the pooled cohort equation. The self-report tool (n=14 variables) and the clinical tool (n=23 variables) showed high-to-excellent discriminative ability to identify a segment involvement score ≥4 (area under the curve 0.79 and 0.80, respectively) and significantly better than the pooled cohort equation (area under the curve 0.76, P<0.001). The tools showed a larger net benefit in clinical decision-making at relevant threshold probabilities. The self-report tool identified 65% of all individuals with a segment involvement score ≥4 in the top 30% of the highest-risk individuals. Tools developed for coronary artery calcification score ≥100 performed similarly. CONCLUSIONS: We have developed a self-report tool that effectively identifies individuals with moderate to severe coronary atherosclerosis. The self-report tool may serve as prescreening tool toward a cost-effective computed tomography-based screening program for high-risk individuals.

Collecting Food and Drink Intake Data With Voice Input: Development, Usability, and Acceptability Study.

BACKGROUND: Voice-based systems such as Amazon Alexa may be useful for collecting self-reported information in real time from participants of epidemiology studies using verbal input. In epidemiological research studies, self-reported data tend to be collected using short, infrequent questionnaires, in which the items require participants to select from predefined options, which may lead to errors in the information collected and lack of coverage. Voice-based systems give the potential to collect self-reported information "continuously" over several days or weeks. At present, to the best of our knowledge, voice-based systems have not been used or evaluated for collecting epidemiological data. OBJECTIVE: We aimed to demonstrate the technical feasibility of using Alexa to collect information from participants, investigate participant acceptability, and provide an initial evaluation of the validity of the collected data. We used food and drink information as an exemplar. METHODS: We recruited 45 staff members and students at the University of Bristol (United Kingdom). Participants were asked to tell Alexa what they ate or drank for 7 days and to also submit this information using a web-based form. Questionnaires asked for basic demographic information, about their experience during the study, and the acceptability of using Alexa. RESULTS: Of the 37 participants with valid data, most (n=30, 81%) were aged 20 to 39 years and 23 (62%) were female. Across 29 participants with Alexa and web entries corresponding to the same intake event, 60.1% (357/588) of Alexa entries contained the same food and drink information as the corresponding web entry. Most participants reported that Alexa interjected, and this was worse when entering the food and drink information (17/35, 49% of participants said this happened often; 1/35, 3% said this happened always) than when entering the event date and time (6/35, 17% of participants said this happened often; 1/35, 3% said this happened always). Most (28/35, 80%) said they would be happy to use a voice-controlled system for future research. CONCLUSIONS: Although there were some issues interacting with the Alexa skill, largely because of its conversational nature and because Alexa interjected if there was a pause in speech, participants were mostly willing to participate in future research studies using Alexa. More studies are needed, especially to trial less conversational interfaces.

COVID-19 Vaccine Hesitancy among Unvaccinated Adults: A Cross-Sectional Exploratory Analysis of Vaccination Intentions in Italy Related to Fear of Infection.

From the initial COVID-19 outbreak, Italy was the first Western country to be seriously affected by the pandemic. Understanding vaccine hesitancy can help efforts to achieve broad vaccination coverage. The objectives of this research were to determine the extent of vaccine hesitancy in Italy and to understand the characteristics of those segments of the population with some hesitancy. Between January and February 2021, 41,473 subjects answered the second questionnaire delivered in phase II of the web-based EPICOVID19 survey. Among the included adult volunteers living in Italy, 4653 (11.2%) reported having previously received at least one dose of the COVID-19 vaccine. In the sample of 36,820 respondents, all not vaccinated (age 51.1 ± 13.5; 59.7% female; 63.6% high level of education), the comparison between hesitant and inclined participants was accompanied by percentages and odds ratios. A total of 2449 individuals were hesitant (6.7% of the unvaccinated ones). Hesitancy was higher among women (OR = 1.48; 95%CI: 1.36-1.62); it was highest in the 50-59 and 40-49 age groups and among those with a lower educational level. A higher level of education was associated with a lower proportion of hesitancy (5.54%) compared with 9.44% among respondents with a low level of education (OR = 0.56; 95%CI: 0.46-0.68). Hesitancy was most common in subjects who did not report fear of infection (12.4%, OR = 4.0; 95%CI: 3.46-4.61). The results can guide the design of tailored information and communication campaigns through considering objective and subjective characteristics.

Opioids and older adults: Increasing trends in opioid usage in a dental population compared to a National Database (NHANES).

AIM: To examine self-reported opioid prevalence at a dental school clinic for patients ≥65 years old as compared to national data, comparing gender, ethnicity/race and older adult age groupings. METHODS AND RESULTS: Self-reported prescription opioid medication use was extracted from the medical record for dental patients ≥65 years old who visited the school's general dental clinic (GDC) in 2012 or 2017. This data was compared to the National Health and Nutrition Examination Survey (NHANES) data for 2011-2012 and 2017-18. There was a significant increase in prevalence of opioid use in adults ≥65 between 2012 (4.5%) and 2017 (6.5%) and for ages 65-79 (from 4.7% to 6.3%) and ≥80 (3.4% to 7.9%), women (4.8% to 7.0%), and African Americans (4.7% to 8.4%) in the GDC. Older adults at the GDC reported less opioid use than the NHANES national average for both periods no matter the gender or the age with variable results for race/ethnicity. CONCLUSION: The prevalence of older adults taking opioids in our general dental school clinic population increased significantly in 2017 as compared to 2012 but was lower than the national average for the respective periods. Awareness of existing opioid usage in older adult patients and its higher adverse risk potential is critical when prescribing analgesics for dental pain for this age group.

Analysing the Relationship Between Immigrant Status and the Severity of Offending Behaviour in Terms of Individual and Contextual Factors.

Background: Social inclusion is a context for both risk and protective factors of migrant youth delinquency. This study aims to shed light on the issue by comparing delinquency amongst native, first-generation, and second-generation immigrant youths in Portugal, a country located in the south of Europe, an area where research in this field is still scarce. Methods: The research is based on the International Self-Reported Delinquency (ISRD-3) dataset, which includes information on over 4,000 adolescents, who self-reported on their socio-demographic status, leisure activities, school and neighbourhood environment, family bonds, and self-control. Results: Nested Logistic Regression analyses showed that a young first-generation immigrant is twice as likely to commit a crime, with or without violence, as a young native born in Portugal. However, no differences were found regarding the prevalence of delinquency amongst second-generation immigrants and natives, which is likely due to the integration and cultural assimilation of the immigrant over time. Regarding the analysed risk factors, it was found that both structural and individual factors, identified by the theories of control, stress, as well as situational action theory, have a direct effect on the commission of juvenile crimes (both non-violent and violent). Moreover, this effect is significant in adolescents living in Portugal in general, both immigrants and natives. The most influential variable for both types of delinquent behaviour, with and without violence, is peer delinquency, followed by low morality and self-control. Conclusion: These findings have relevant policy implications and are useful for evidence-based interventions aimed at promoting migrant adolescent well-being and targeting host countries' performance.

Identification of Major Cognitive Disorders in Self-Reported versus Administrative Health Data: A Cohort Study in Quebec.

BACKGROUND: The first imperative in producing the relevant and needed knowledge about major neurocognitive disorder (MNCD) is to identify people presenting with the condition adequately. To document potential disparities between administrative health databases and population-based surveys could help identify specific challenges in this population and methodological shortfalls. OBJECTIVE: To describe and compare the characteristics of community-dwelling older adults according to four groups: 1) No MNCD; 2) Self-reported MNCD only; 3) MNCD in administrative health data only; 4) MNCD in both self-reported and administrative health data. METHODS: This retrospective cohort study used the Care Trajectories-Enriched Data (TorSaDE) cohort, a linkage between five waves of the Canadian Community Health Survey (CCHS) and health administrative health data. We included older adults living in the community who participated in at least one cycle of the CCHS. We reported on positive and negative MNCD in self-reported versus administrative health data. We then compared groups' characteristics using chi-square tests and ANOVA. RESULTS: The study cohort was composed of 25,125 older adults, of which 784 (3.1%) had MNCD. About 70% of people with an MNCD identified in administrative health data did not report it in the CCHS. The four groups present specific challenges related to the importance of perception, timely diagnosis, and the caregivers' roles in reporting health information. CONCLUSION: To a certain degree, both data sources fail to consider subgroups experiencing issues related to MNCD; studies like ours provide insight to understand their characteristics and needs better.

Epidemiology of SARS-CoV-2 Infection in Italy Using Real-World Data: Methodology and Cohort Description of the Second Phase of Web-Based EPICOVID19 Study.

Digital technologies have been extensively employed in response to the SARS-CoV-2 pandemic worldwide. This study describes the methodology of the two-phase internet-based EPICOVID19 survey, and the characteristics of the adult volunteer respondents who lived in Italy during the first (April-May 2020) and the second wave (January-February 2021) of the epidemic. Validated scales and ad hoc questionnaires were used to collect socio-demographic, medical and behavioural characteristics, as well as information on COVID-19. Among those who provided email addresses during phase I (105,355), 41,473 participated in phase II (mean age 50.7 years ± 13.5 SD, 60.6% females). After a median follow-up of ten months, 52.8% had undergone nasopharyngeal swab (NPS) testing and 13.2% had a positive result. More than 40% had undergone serological test (ST) and 11.9% were positive. Out of the 2073 participants with at least one positive ST, 72.8% had only negative results from NPS or never performed it. These results indicate that a large fraction of individuals remained undiagnosed, possibly contributing to the spread of the virus in the community. Participatory online surveys offer a unique opportunity to collect relevant data at individual level from large samples during confinement.

Mean corrected generalized estimating equations for longitudinal binary outcomes with report bias.

Cocaine addiction is an important public health problem worldwide. Cognitive-behavioral therapy is a counseling intervention for supporting cocaine-dependent individuals through recovery and relapse prevention. It may reduce patients' cocaine uses by improving their motivations and enabling them to recognize risky situations. To study the effect of cognitive behavioral therapy on cocaine dependence, the self-reported cocaine use with urine test data were collected at the Primary Care Center of Yale-New Haven Hospital. Its outcomes are binary, including both the daily self-reported drug uses and weekly urine test results. To date, the generalized estimating equations are widely used to analyze binary data with repeated measures. However, due to the existence of significant self-report bias in the self-reported cocaine use with urine test data, a direct application of the generalized estimating equations approach may not be valid. In this paper, we proposed a novel mean corrected generalized estimating equations approach for analyzing longitudinal binary outcomes subject to reporting bias. The mean corrected generalized estimating equations can provide consistently and asymptotically normally distributed estimators under true contamination probabilities. In the self-reported cocaine use with urine test study, accurate weekly urine test results are used to detect contamination. The superior performances of the proposed method are illustrated by both simulation studies and real data analysis.

Assessing the consistency and validity of self-reported year of diagnosis among participants in a longitudinal study of people with multiple sclerosis.

BACKGROUND: Self-reported outcomes are important for epidemiological research but are vulnerable to bias. OBJECTIVE: In this study, we evaluated: 1) the consistency and validity of self-reported year of diagnosis among people living with MS, 2) factors associated with participant inconsistency, and 3) the impact of observed inconsistency on the calculation of the Multiple Sclerosis Severity Score (MSSS). METHODS: Using data collected by the Australian MS Longitudinal Study, we evaluated the consistency of self-reported year of diagnosis using correlation, mean differences, and percentage agreement. We examined the impact of participant characteristics using Cragg hurdle models, and determined the effect of the observed inconsistency on MSSS using simulations compared with paired t-tests. RESULTS: Of the 2,445 participants, 80.3% were within 1 year of their baseline year of diagnosis in all subsequent responses (range of 2-10 responses). Participant inconsistency was positively associated with age at first response and the number of years elapsed between the first and final response. However, the effect sizes of these associations were small. Finally, the observed inconsistency did not affect the calculation of MSSS (mean difference smaller than 0.01; p>0.90 for all comparisons). CONCLUSION: This data provides support for the use of patient-reported year of diagnosis, as people with MS were consistent in reporting their year of diagnosis and the impact of any inconsistency on clinical outcomes, such as the MSSS, was negligible.

What Accounts for Physical Activity during Pregnancy? A Study on the Sociodemographic Predictors of Self-Reported and Objectively Assessed Physical Activity during the 1st and 2nd Trimesters of Pregnancy.

Physical activity (PA) during pregnancy has positive health implications for both mother and child. However, current literature indicates that not all pregnant women meet the international recommendations for PA (at least 150 min/week of moderate-to-vigorous PA). The main objective of this study was to assess PA levels among pregnant women in the city of Donostia-San Sebastian and identify their main sociodemographic predictors. We recruited 441 women in the 12th week of pregnancy from the local public obstetric health services. Women wore an accelerometer for one week during two separate time points (1st and 2nd trimesters of pregnancy) and completed a questionnaire assessing several sociodemographic variables as well as self-reported PA. With this information, we estimated women's overall PA levels during both time points. The fulfillment of PA recommendations raised up to 77% and 85% during the first and second trimesters, respectively. We found that a higher number of children and a greater preference for exercise positively predicted light-to-moderate PA, being the most consistent predictors. The availability of a greater number of cars negatively predicted moderate-to-vigorous PA.