Determinants Of Dropout Research Articles

Determinants of measles second dose vaccination dropout among children aged 18-24 months in Ejere woreda, central Ethiopia; unmatched case-control study.

Measles continues to pose a significant public health challenge, especially in low- and middle-income countries. Despite the implementation of national vaccination programs, measles outbreaks persist in some parts of Ethiopia, and the determinants of dropout from the second measles vaccine dose are not well understood. Hence, this study aimed to assess determinants of measles second dose vaccination dropout among children aged 18-24 months in Ejere woreda, central Ethiopia. A community-based unmatched case-control design was conducted in the Ejere Woreda of the Oromia regional state in Ethiopia between February 14 and April 6, 2023. Data were collected using a pre-tested structured questionnaire. The collected data were coded and entered into Epi-data version 3.1 and then transported to SPSS version 27 for statistical analysis. Descriptive analysis like frequency, mean, and percentage was calculated. Binary and multivariable logistic regression analysis was done. Finally, variables with a p-value <0.05 were considered statistically significant. A total of 446 mothers/caregivers, comprising 110 cases and 336 controls, participated in this study, making the response rate 97.8%. Lack of a reminder for the measles vaccine during postnatal care (PNC) (AOR = 5.19; 95% CI: 2.34, 7.83), having ≤2 antenatal care (ANC) contacts (AOR = 4.95; 95% CI: 2.86, 9.24), long waiting times during previous vaccination (AOR = 2.78; 95% CI: 1.19, 4.38), children of mothers/caregivers without formal education (AOR = 6.46; 95% CI: 2.81, 11.71), mothers/caregivers of children who were unaware of the importance of the second dose of measles (AOR = 8.37; 95% CI: 4.22, 15.08), and mothers/caregivers whose children did not receive at least two doses of vitamin A (AOR = 4.05; 95% CI: 2.15, 8.11) were significant determinants of measles second dose vaccination dropout. Implementing targeted interventions during antenatal care and when mothers visit health facilities for other vaccines can significantly improve the uptake of the second dose of the measles vaccine. These strategies not only enhance overall vaccination coverage but also mitigate the risk of measles outbreaks in the community.

Determinants of dropout and compliance of children participating in a multidisciplinary intervention programme for overweight and obesity in socially deprived areas.

Children with overweight and obesity in socially deprived areas (SDAs) are less likely to complete and be compliant to a weight-loss programme. To identify factors associated with dropout and compliance of a multidisciplinary weight-loss programme in SDA. This prospective longitudinal cohort study included children (6-12 years) with overweight and obesity in a 12-week multidisciplinary intervention living in SDA in Rotterdam, the Netherlands. Potential predictive variables for dropout and compliance included were age, sex, the weight of the child and parents, quality of life, and referral status (self-registration or referral). A Cox proportional hazards model was performed to study the association between dropout and its potential predictive variables, whereas logistic regression analyses were used for the potential predictors for compliance. A total of 121 children started the intervention programme. Forty-one (33.9%) children dropped out and 68 (56.2%) were compliant with the intervention. The risk of dropping out of the intervention was significantly lower for a child with overweight parents than for those with parents with normal weight (adjusted hazard ratio [HR] 0.22 [95% confidence interval, CI 0.063-0.75]), and for those with parents with obesity (adjusted HR 0.18 [95% CI 0.060-0.52]). No other potential predictive variables were associated with dropout or compliance. Children from SDA participating in a weight-loss programme have a relatively high dropout and a low compliance rate. Parental weight seems to be an important predictor for dropout of children from SDA, where children with normal weight or obese parents have the highest risk of dropout compared with children of overweight parents.

Emergency department consultations for respiratory symptoms revisited: exploratory investigation of longitudinal trends in patients\u2019 perspective on care, health care utilization, and general and mental health, from a multicenter study in Berlin, Germany

BackgroundOnly few studies of emergency department (ED) consulters include a longitudinal investigation. The EMACROSS study had surveyed 472 respiratory patients in eight inner-city EDs in Berlin in 2017/2018 for demographic, medical and consultation-related characteristics. This paper presents the results of a follow-up survey at a median of 95 days post-discharge. We aimed to explore the post hoc assessment of ED care and identify potential longitudinal trends.MethodsThe follow-up survey included items on satisfaction with care received, benefit from the ED visit, potential alternative care, health care utilization, mental and general health, and general life satisfaction. Univariable between-subject and within-subject statistical comparisons were conducted. Logistic regression was performed for multivariable investigations of determinants of dropout and of retrospectively rating the ED visit as beneficial.ResultsFollow-up data was available for 329 patients. Participants of lower education status, migrants, and tourists were more likely to drop out. Having a general practitioner (GP), multimorbidity, and higher general life satisfaction were determinants of response. Retrospective satisfaction ratings were high with no marked longitudinal changes and waiting times as the most frequent reason for dissatisfaction. Retrospective assessment of the visit as beneficial was positively associated with male sex, diagnoses of pneumonia and respiratory failure, and self-referral. Concerning primary care as a viable alternative, judgment at the time of the ED visit and at follow-up did not differ significantly. Health care utilization post-discharge increased for GPs and pulmonologists. Self-reported general health and PHQ-4 anxiety scores were significantly improved at follow-up, while general life satisfaction for the overall sample was unchanged.ConclusionsMost patients retrospectively assess the ED visit as satisfactory and beneficial. Possible sex differences in perception of care and its outcomes should be further investigated. Conceivable efforts at diversion of ED utilizers to primary care should consider patients’ views regarding acceptable alternatives, which appear relatively independent of situational factors. Representativeness of results is restricted by the study focus on respiratory symptoms, the limited sample size, and the attrition rate.Trial registrationGerman Clinical Trials Register (DRKS00011930); date: 2017/04/25.

Determinants of Dropout from and Variation in Adherence to an Exercise Intervention: The STRRIDE Randomized Trials.

This study aimed to characterize the timing and self-reported determinants of exercise dropout among sedentary adults with overweight or obesity. We also sought to explore variations in adherence among individuals who completed a 6- to 8-month structured exercise intervention. A total of 947 adults with dyslipidemia [STRRIDE I, STRRIDE AT/RT] or prediabetes [STRRIDE-PD] were enrolled to either control or to one of 10 exercise interventions, ranging from doses of 8-23 kcal/kg/week; intensities of 50%-75% V̇O2 peak; and durations of 6-8 months. Two groups included resistance training and one included dietary intervention (7% weight loss goal). Dropout was defined as an individual who withdrew from the study due a variety of determinants. Timing of intervention dropout was defined as the last session attended and categorized into phases. Exercise training adherence was calculated by dividing weekly minutes or total sets of exercise completed by weekly minutes or total sets of exercise prescribed. General linear models were used to characterize the associations between timing of dropout and determinant category. Compared to exercise intervention completers (n=652), participants who dropped out (n=295) were on average non-white (98% vs. 80%, p<0.01), had higher body mass index (31.0 kg/m2 vs. 30.2 kg/m2; p<0.01), and were less fit at baseline (25.0 mg/kg/min vs. 26.7 ml/kg/min, p<0.01). Of those who dropped out, 67% did so prior to the start of or while ramping up to the prescribed exercise volume and intensity. The most commonly reported reason for dropout was lack of time (40%). Notably, among individuals who completed the ramp training period, subsequent exercise intervention adherence did not waiver over the ensuing 6-8 months of training. These findings are some of the first to delineate associations between the timing of dropout and dropout determinants, providing guidance to future exercise interventions to better support individuals at-risk for dropout.

Magnitude and Determinants of Dropout from Community-Based Health Insurance Among Households in Manna District, Jimma Zone, Southwest Ethiopia.

BackgroundCommunity-based health insurance (CBHI) is a prepayment method of financial contributions for healthcare which aims to risk pooling, avoidance of catastrophic and impoverishing health expenditure. However, a high dropout from the scheme remains the biggest challenge to effective and sustainable progress towards universal financial protection in low- and middle-income countries. While large literature had examined initial enrollment and factors associated with it, only a few studies dealt with dropout. So the study aimed to assess the magnitude and determinants of dropout from community-based health insurance among households in Manna district, Jimma zone, Oromia Regional State, Ethiopia.MethodsA community-based cross-sectional study design was employed to collect data from 634 household heads from March 1 to 30, 2020. A multistage sampling technique was carried out and interviewer-administered questionnaires were used to collect data. Descriptive statistics and multivariable logistic regression analyses were performed, and variables with a P-value<0.05 were considered as having a statistically significant association with the dropout from the CBHI.ResultsMagnitude of dropout from CBHI was 31.9% with 95% confidence interval (CI)=28.2–35.8% and relatively older age [adjusted odds ratio (AOR) (95% CI)=0.26 (0.10–0.78)], educational level [AOR (95% CI)=0.16 (0.06–0.41)], family size [AOR (95% CI)=0.36 (0.19–0.66)], poor perceived quality of service [AOR (95% CI)=5.7 (2.8–11.8)], trust in health facility [AOR (95% CI)=0.43 (0.3–0.61)], trust in the scheme [AOR (95% CI)=0.61 (0.45–0.84)], providers’ attitude [AOR (95% CI)=10 (4.0–25.4)], and benefit package [AOR (95% CI)=4.9 (2.4–9.9)] were statistically significant determinants associated with dropout.ConclusionDropout from CBHI in this study area was high. Household heads’ age, educational level, family size, perceived quality of service, providers’ attitude, a benefits package, trust in the contracted health facility, and the scheme were the significant predictors of dropout. We strongly recommend that greater efforts should be made toward the providers’ attitude, promised benefit package, and quality of services.

Patterns of care and dropout rates from outpatient mental healthcare in low-, middle- and high-income countries from the World Health Organization's World Mental Health Survey Initiative.

There is a substantial proportion of patients who drop out of treatment before they receive minimally adequate care. They tend to have worse health outcomes than those who complete treatment. Our main goal is to describe the frequency and determinants of dropout from treatment for mental disorders in low-, middle-, and high-income countries. Respondents from 13 low- or middle-income countries (N = 60 224) and 15 in high-income countries (N = 77 303) were screened for mental and substance use disorders. Cross-tabulations were used to examine the distribution of treatment and dropout rates for those who screened positive. The timing of dropout was examined using Kaplan-Meier curves. Predictors of dropout were examined with survival analysis using a logistic link function. Dropout rates are high, both in high-income (30%) and low/middle-income (45%) countries. Dropout mostly occurs during the first two visits. It is higher in general medical rather than in specialist settings (nearly 60% v. 20% in lower income settings). It is also higher for mild and moderate than for severe presentations. The lack of financial protection for mental health services is associated with overall increased dropout from care. Extending financial protection and coverage for mental disorders may reduce dropout. Efficiency can be improved by managing the milder clinical presentations at the entry point to the mental health system, providing adequate training, support and specialist supervision for non-specialists, and streamlining referral to psychiatrists for more severe cases.

DETERMINANTS OF MIDDLE CLASS SCHOOL DROPOUT AMONG BOYS IN THE RIYADH PROVINCE OF SAUDI ARABIA

Purposes: This study examines the determinants of middle-income school dropouts in Saudi Arabia. The determinants of dropouts are fairly similar across many countries worldwide and this has made the issue of dropouts a global phenomenon. However, the situation in Gulf countries is different because these countries accord special treatment to male children but not to female children. This directly affects the educational pursuit of male children in the region. Saudi Arabia was empirically studied and a sample of 360 respondents was investigated. The respondents were drawn randomly from each of the 11 secondary night schools.&#x0D; Methodology: The method used for analysis in this study was a combination of descriptive statistics involving cross-tabulations and simple multivariate logistic regression. The results showed that the majority of the dropouts are aged between 15 and 32 years.&#x0D; Results: The regression results showed that absenteeism, educational targets, and value have a significant relationship with school completion. These results may be connected to the findings of the Dubai School of Government in 2011, which indicated that male pursuit of employment opportunities was of greater significance in achieving social and economic mobility compared to educational achievement. This suggests that Saudi males prioritize employment opportunities over educational achievements.&#x0D; Implications/Applications: On the other hand, there are also those who place value on education and will make the effort to complete their school education in Saudi Arabia.&#x0D; Novelty/Originality: Thos finding reveals a significant correlation between school completion and educational value. The implication is that male student who values education are more likely to complete school in comparison with those who do not value education. Efforts must be intensified to promote retention and create awareness among the young people of the benefits of education in the long run.

Determinants of Dropout and Child School Enrollment: A Case Study from Rural Islamabad

Education is an important pillar for the development of any society. Generally, school enrollment in developing countries is observed very low compared to the developed countries and the situation is further worsened by the high dropout rate. The current study investigates the major factors responsible for high dropouts in Islamabad, Pakistan, particularly in rural areas. For this purpose, the primary data have been obtained through a detailed questionnaire collecting information on child socioeconomic, household, cultural, and other characteristics. For modeling purposes, Probit model is used to investigate the effects of various factors on high child dropout rate. The results revealed that besides the distance from school to home, financial constraints are the most important reason for dropping out. Moreover, the education of father, age of the child and the gender of the child are also highly significant variables that determine the probability of a child dropout.

Determinants of Dropout From Correctional Offender Treatment

Research indicates that approximately one third of offenders admitted to social-therapeutic correctional facilities in Germany fail to complete treatment and that treatment dropout is linked to higher recidivism in both sexual and violent offenders. The purpose of this study was to examine determinants of treatment dropout in a social-therapeutic correctional facility in Germany. The sample consisted of 205 incarcerated adult male offenders (49.8% sexual, 38.1% non-sexual violent) admitted to correctional treatment. Completers and dropouts were compared on variables pertaining to demographics, offense type, substance abuse, psychopathy, risk, and protective factors. Univariate analyses showed that treatment dropouts demonstrated significantly higher scores on measures of risk and psychopathy and lower scores on protective factors. Logistic regression analyses identified unemployment, non-sexual violent index offense, higher risk scores (HCR-20), and Facet 1 (interpersonal deficits) of the Psychopathy Checklist-Revised (PCL-R) as significant predictors of treatment dropout. Surprisingly, substance abuse disorder was a negative predictor of dropout. With the exception of substance abuse, the results support the notion that treatment dropouts represent a group of high-risk offenders with particular treatment needs. Practical implications and suggestions for further research are discussed.

Determinants of drop-out in youth basketball: an interdisciplinary approach

ABSTRACTUsing an interdisciplinary approach, we examined the baseline variation in biological maturity status, training experience, body size, functional capacities (Line Drill test and Yo-Yo Intermittent Recovery level 1 test) and motivation for achievement, competitiveness and deliberate practice of youth basketball players according to their participation status in the sport two years after assessment. Fifty-seven players were considered (10.5 to 15.5 years). Two years later we ascertained whether players discontinued participation (dropout), or remained playing engaged within a structured basketball training program. Taller adolescent players were more likely to be selected/promoted in youth basketball regardless of their lower functional capacity. Achievement and competitiveness motivation (will to excel and competitiveness) were related to dropping out or persisting in this sample of youth basketball players. Overall, there is a need to consider the interaction between physical growth, biological maturation, functional capacities and behavioural characteristics, specifically among players on the path to sport expertise.

Time-use and environmental determinants of dropout from organized youth football and tennis

BackgroundMany adolescents drop out of organized sports. Lack of motivation and competing priorities are known as important reasons for dropout. However, time use factors as well as environmental determinants have been largely neglected in the current literature on dropout from youth sports. The aim of this study is to investigate how (changes in) time use and characteristics of the physical environment determine dropout from football and tennis among adolescents.MethodsData on time use and background characteristics were collected through online surveys in 2015 and 2016 among adolescents aged 13–21 (N = 2555), including both the dropped outs and those who still continued membership of their football or tennis clubs. Physical environmental determinants (travel distance to the sports club, and neighbourhood density) were measured objectively. Binary logistic regression analyses were carried out for football and tennis separately to examine the associations between time use (time spent on various activities and changes related to the school and job situation), and environmental factors on the probability of dropping out from sports.ResultsTime spent on sports outside the context of the sports club, and time spent on social or voluntary activities at the sports club was positively associated with continuing being football and tennis members. Tennis players who changed schools or participated in two sports at the same time had a higher probability of dropping out, whereas tennis players who travelled greater distances from home to the tennis club were less likely to drop out.ConclusionsDeterminants of dropout differed between football and tennis. However, time use variables were important predictors of dropout from football as well as tennis, whereas environmental determinants hardly contributed to the prediction of dropout. To keep youths involved in organized sports, this study recommends that sports professionals should: 1) offer flexibility in training and competition schedules, 2) stimulate participation in social activities and voluntary work at the sports club, 3) pay special attention to their needs and preferences, and 4) encourage possibilities to practice and play sports outside of regular training hours, for instance at the sports club or at playgrounds or parks in the neighbourhood.

Comorbidities and Psychosocial Characteristics as Determinants of Dropout in Outpatient Cardiac Rehabilitation.

Despite the clear benefits of cardiac rehabilitation (CR), a considerable number of patients drop out early. Therefore, we wanted to evaluate dropout in CR with a special focus on comorbidities and psychosocial background. Patients who attended CR after acute coronary syndrome, cardiac surgery, or heart failure (N = 489) were prospectively included. Dropout was defined as attending 50% of the training sessions or less (n = 96 [20%]). Demographic and clinical characteristics, exercise parameters, and psychosocial factors were analyzed according to dropout, and those with a trend toward a significant difference (P < .10) were entered in a multivariate logistic model. The presence of a cerebrovascular accident (4.18 [1.39-12.52]) involved a higher risk of dropout, and a comparable trend was seen for the presence of chronic obstructive pulmonary disease (2.55 [0.99-6.54]). Attending the training program only twice per week also implicated a higher risk of an early withdrawal (3.76 [2.23-6.35]). In contrast, patients on β-blockers were less likely to withdraw prematurely (0.47 [0.22-0.98]). Singles were more likely to drop out (2.89 [1.56-5.35]), as well as those patients who were dependent on others to get to CR (2.01 [1.16-3.47]). Finally, the reporting of severe problems on the anxiety/depression subscale of the EuroQOL-5D questionnaire involved a higher odds for dropout (7.17 [1.46-35.29]). Neither demographic characteristics nor clinical status or exercise capacity could independently identify patients who were at risk of dropout. The presence of comorbidities and a vulnerable psychosocial background rather seem to play a key role in dropout.

Determinants of Student Dropouts: A Case Study of Business Students

This study attempts to explore the reasons behind students' dropouts from higher education business schools. For this purpose, data about 1200 students over a period of one year is collected and analyzed from a leading business school in Peshawar. Determinants of dropouts are extracted from the literature and are tested for their association with the dropout decision by the students. Findings of the study are partially aligned with the literature and prove a significant relationship between gender, the type of school attended, students' performance at the SSC and HSSC levels, and major subjects studied at the HSSC level with the incidence of students' dropout from the business school; whereas age, father income, and hometown has shown no relationship with the students' dropout from the business school

Patterns and determinants of dropout from maternity care continuum in Nigeria.

BackgroundThe maternal, newborn and child health care continuum require that mother/child pair should receive the full package of antenatal, intrapartum and postnatal care in order to derive maximum benefits. Continuity of care is a challenge in sub-Saharan Africa. In this study, we investigate the patterns and factors associated with dropout in the continuum of maternity (antenatal, delivery and postnatal) care in Nigeria.MethodUsing women recode file from the 2013 Nigeria Demographic and Health Survey, we analysed data on 20,467 women with an index birth within 5 years prior to data collection. Background characteristics and pattern of dropouts were summarised using descriptive statistics. The outcome variable was dropout which we explored in three stages: antenatal, antenatal-delivery, delivery-6 weeks postnatal visit. Multilevel logistic regression models were fitted to identify independent predictors of dropout at each stage. Measure of effect was expressed as Odds Ratio (OR) with 95 % confidence interval (CI).ResultsOverall, 12,392 (60.6 %) of all women received antenatal care among whom 38.1 % dropout and never got skilled delivery assistance. Of those who received skilled delivery care, 50.8 % did not attend postnatal visit. The predictors of dropout between antenatal care and delivery include problem with getting money for treatment (OR = 1.18, CI: 1.04–1.34), distance to health facility (OR = 1.31, CI: 1.13–1.52), lack of formal education, being in poor wealth quintile (OR = 2.22, CI: 1.85–2.67), residing in rural areas (OR = 1.98, CI: 1.63–2.41). Regional differences between North East, North West and South West were significant. Between delivery and postnatal visit, the same factors were also associated with dropout.ConclusionThe rate of dropout from maternity care continuum is high in Nigeria and driven by low or lack of formal education, poverty and healthcare access problems (distance to facility and difficulty with getting money for treatment). Unexpectedly, dropouts are high in South east and South south as well as in the Northern regions. Intervention programs focusing on community outreach about the benefits of continuum of maternal healthcare package should be introduced especially for women in rural areas and lower socio-economic strata.

Determinants of dropout in a community-based mental health crisis centre.

BackgroundDropping out during the course of medical follow up is defined as an early therapy withdrawal without the agreement of the therapist. In a psychiatric crisis unit in Geneva, we empirically observed that almost 50 % of the patients were not showing up to their first appointments, which were scheduled for 3 to 7 days post discharge.MethodsThe aim of this naturalistic descriptive cohort study is to identify the demographic, patient and care-related predictive factors of dropout in a community-based psychiatric crisis centre. We included 245 consecutive outpatients followed-up for 4 to 6 weeks of intensive outpatient psychiatric treatment. Logistic regression models were built to examine the association between dropout and demographic, care and patient-related variables.ResultsAmong the 245 outpatients, dropout occurred in 37.5 % of cases, and it most frequently occurred (81.8 %) in the first 2 days of follow-up. Among care-related variables, referral by hospital units or private psychiatrists led to significantly lower levels of dropout compared to patients referred by the psychiatric emergency unit (respectively: OR = .32; p = .04; 95 % CI [.10, .93]; OR = .36; p = .04; 95 % CI [.13, .96]; OR = .22; p = .002; 95 % CI [.08, .58]). Among patient-related variables, younger age increased the risk of dropout (OR = .96; 95 %; p = .002; 95 % CI [.94, .99]). Anxiety and personality but not mood disorders were also related to higher rates of dropout (respectively: OR = 2.40; p = .02; 95 % CI [1.14, 4.99]; and OR = 1.98; p = .02; 95 % CI [1.09, 3.59]). Unipolar depression (72.2 %; OR = 1.47; p = .48; 95 % CI [.34, 1.21]) was the most frequent primary diagnosis in this sample.ConclusionsThis study makes clear the need for increased efforts to improve care adherence in young patients with anxious or personality disorders seen in emergency rooms because they are prone to early discontinuation of treatments. Future studies in this field are warranted to gain a better understanding into the complex reasons that surround discontinuation of care in outpatient settings.

Determinants of Drop-out among Public Islamic School Girls in the Techiman Municipality

The study was to investigate into the factors that inform decisions for Islamic girl children to drop out of school, with special reference to parental attitude. Data were collected using questionnaire and structured interview. Fifty Techiman girl children of the Islamic background and their parents who were randomly selected formed the population for the study. Data were analysed using multiple regression and frequency tables. The findings of the study point to five factors two of which are social in nature and three of which are academic in nature, as responsible for the high rate of dropout among Islamic school girls in the Techiman municipality. The study established that contrary to the general perception that parents have to be blamed for dropout among school girls, parent of these Islamic schools girls have positive attitude towards their wards’ education. Discussion of the result were made and conclusions drawn. Recommendations were made.

Beginning and end of treatment of patients who dropped out of psychoanalytic psychotherapy.

Even though it is expected that patients and therapist will agree on when to terminate psychotherapy, quite often patients discontinue treatment on their own. This study aims to better understand dropout in psychoanalytic psychotherapy (PP). Baseline and post-treatment interviews were conducted with six adult women classified by their therapists as dropout patients at a PP outpatient clinic. Results were analyzed using Bardin's content analysis. Content analysis generated five categories (reasons for treatment, goals, readiness to change, previous treatment, transference) for the baseline interviews and three categories (change process, results, interruption) for post-treatment interviews. Unclear treatment goals, low readiness to change, early signs of negative transference and resistance, and absence of recognition of their own participation in problems emerged in baseline interviews. In most cases, the patient's evaluation of the therapeutic relationship was not determinant of dropout. Therapeutic gains, dissatisfaction, and resistance during the psychotherapeutic process seemed to be associated with noncompliance. Decisions to initiate, continue, or quit PP depend on multiple factors, such as initial goals, readiness to change, insight capacity, awareness of personal problems, resistance, and transference. However, these factors should be considered in view of the methodological limitations of this study. Further investigation of PP dropout is still necessary.

Marginal Structural Models for Case-Cohort Study Designs to Estimate the Association of Antiretroviral Therapy Initiation With Incident AIDS or Death

To estimate the association of antiretroviral therapy initiation with incident acquired immunodeficiency syndrome (AIDS) or death while accounting for time-varying confounding in a cost-efficient manner, the authors combined a case-cohort study design with inverse probability-weighted estimation of a marginal structural Cox proportional hazards model. A total of 950 adults who were positive for human immunodeficiency virus type 1 were followed in 2 US cohort studies between 1995 and 2007. In the full cohort, 211 AIDS cases or deaths occurred during 4,456 person-years. In an illustrative 20% random subcohort of 190 participants, 41 AIDS cases or deaths occurred during 861 person-years. Accounting for measured confounders and determinants of dropout by inverse probability weighting, the full cohort hazard ratio was 0.41 (95% confidence interval: 0.26, 0.65) and the case-cohort hazard ratio was 0.47 (95% confidence interval: 0.26, 0.83). Standard multivariable-adjusted hazard ratios were closer to the null, regardless of study design. The precision lost with the case-cohort design was modest given the cost savings. Results from Monte Carlo simulations demonstrated that the proposed approach yields approximately unbiased estimates of the hazard ratio with appropriate confidence interval coverage. Marginal structural model analysis of case-cohort study designs provides a cost-efficient design coupled with an accurate analytic method for research settings in which there is time-varying confounding.

Modeling Dropout From Adverse Event Data: Impact of Dosing Regimens Across Pregabalin Trials in the Treatment of Generalized Anxiety Disorder

Dizziness represents a major determinant of dropout in the treatment of generalized anxiety disorder with pregabalin. Titration (dose escalation) regimens based on clinical judgment were implemented to mitigate this adverse event and reduce patient dropout across clinical trials. Dropout is an important treatment failure endpoint, which can be analyzed using time-to-event models that incorporate daily dosing or other time-varying information. A parametric discrete-time dropout model with daily dizziness severity score as a covariate afforded a systematic, model-based assessment of titration dosing strategies, with model predictions evaluated against corresponding nonparametric estimates. A Gompertz hazard function adequately described the decreasing dropout hazard over time for individuals with severe or moderate dizziness and a lower, constant hazard for individuals reporting no dizziness or mild dizziness. Predictive performance of the model was adequate based on external validation with an independent trial and other goodness-of-fit criteria. Prospective simulations highlight the utility of this approach in reducing dropout based on examination of untested titration scenarios for future generalized anxiety disorder or other trials.

An eating disorder randomized clinical trial and attrition: Profiles and determinants of dropout

This study sought to determine whether differential treatment effects in the targeted mechanisms of change and eating disorder (ED) symptoms are associated with patterns of attrition from a RCT. The main study was a RCT of a psychotherapy designed to alter the non-weight related self-cognitions as the means to promote recovery and health in a sample of 69 women with AN or BN. Four groups based on point of dropout were compared on demographic, self-cognitions and ED symptoms using logit and piecewise mixed effects modeling. Attrition was highest during treatment phase but no significant predictors were found. During the measurement phase, the direction and amount of change in self-cognition interrelatedness and body dissatisfaction differed according to point of dropout and treatment group. Attention to changes both in symptoms and mediating factors that occur during treatment and follow-up may help to identify those who are at risk for dropout and to develop strategies to promote RCT participant retention.