How Health Professionals Conceptualize and Represent Placebo Treatment in Clinical Trials and How Their Patients Understand It: Impact on Validity of Informed Consent.

CONTEXT: Previous studies suggested that many patients, who have given their informed consent to participate in randomized controlled trials (RCT), have somewhat limited understanding of what a placebo treatment is. We hypothesized that the relationship between patients and their health professionals plays a central role in this understanding. METHODS: We interviewed 12 patients included in RCTs (nine suffering from Parkinson's disease and three from Huntington's disease) and 18 health professionals involved with RCTs (eight principal investigators, four associated physicians and six clinical research associates). Semi-structured interviews were conducted after the RCTs had ended but before the treatment allocation was revealed. RESULTS: Only two patients clearly understood the aim of placebo-controlled RCTs. Only one principal investigator said she asks all her patients whether they agree to participate in RCTs. The seven others said they only ask patients who seem more likely to be compliant. Their selection criteria included docility and personality traits associated in other studies with enhanced placebo responses. According to 13 of the 18 health professionals, their relationship with patients may influence the amplitude of the placebo response. All but one clinical research associates added that the placebo response could result from a "maternal" type of care. All principal investigators said they have a strong influence on their patient's decision to participate. Finally, when interviewees were asked to narrate a memory of a medically unexplained healing, in eight of 11 physicians' narratives the beneficiary was a child while in 10 of 12 patients' narratives it was an adult. CONCLUSION: Our observations suggest that the interrelationship between health professionals and patients involved in RCTs could be compared to that between parents and children. Therefore, adherence to formal rules regarding informed consent does not ensure a balanced relationship between patients and health professionals.

Factors associated with missing data in an experience sampling investigation of substance use determinants.

BACKGROUND: The Experience Sampling Method (ESM) collects data repeatedly over time, and is therefore prone to missing observations. Little is known about the characteristics of the subjects and of the ESM procedure associated with unanswered records. Through an ESM investigation of substance use determinants, these characteristics were able to be analyzed. METHODS: Participants (n=224) were undergraduate university students enrolled for a study of substance use factors, providing data through the use of classic questionnaires and through the Experience Sampling Method (ESM) using palmtop computers. For the ESM, they were signaled five times per day for 7 days (7840 records). Characteristics of the ESM procedure and of the participants were analyzed jointly. The probability of an unanswered ESM record was analyzed using a random-intercept logistic regression, fitting a multivariate mixed-effect model for repeated measurements. RESULTS: Factors significantly associated with an unanswered record were: male gender, being a Sport Science student, having higher scores of novelty seeking and of persistence, and being a poly-substance user. Unanswered records were also more frequent in the middle of the week and at the beginning of the day. CONCLUSION: Findings are discussed in term of the possible impact of missing observations. In particular, the lower compliance of poly-substance users with the ESM protocol may curtail the validity of the method, since ESM records are less representative of all moments in these persons daily life. Thus, results from ESM studies of substance use should be regarded cautiously and complemented with other data gathering procedures.

Computerized ambulatory monitoring in psychiatry: a multi-site collaborative study of acceptability, compliance, and reactivity.

Computerized ambulatory monitoring overcomes a number of methodological and conceptual challenges to studying mental disorders, however concerns persist regarding the feasibility of this approach with severe psychiatric samples and the potential of intensive monitoring to influence data quality. This multi-site investigation evaluates these issues in four independent samples. Patients with schizophrenia (n = 56), substance dependence (n = 85), anxiety disorders (n = 45), and a non-clinical sample (n = 280) were contacted to participate in investigations using computerized ambulatory monitoring. Micro-computers were used to administer electronic interviews several times per day for a one-week period. Ninety-five percent of contacted individuals agreed to participate in the study, and minimum compliance was achieved by 96% of these participants. Seventy-eight percent of all programmed assessments were completed overall, and only 1% of micro-computers were not returned to investigators. There was no evidence that missing data or response time increased over the duration of the study, suggesting that fatigue effects were negligible. The majority of variables investigated did not change in frequency as a function of study duration, however some evidence was found that socially sensitive behaviors changed in a manner consistent with reactivity.

The relation between social behavior and negative affect in psychosis-prone individuals: an experience sampling investigation.

Daily social behavior and negative affect were examined in a sample of individuals with a wide spectrum of psychosis-proneness scores. Using the experience sampling method, participants were signaled five times per day for a 1-week period to provide naturalistic reports of location, activity, and social behavior. Little evidence was found for a direct association between psychosis-proneness and specific behavioral profiles, but individuals with higher scores of psychosis-proneness reported spending more time doing nothing or waiting. However, the levels of anxious and depressed moods experienced in certain social and environmental contexts were also predicted by psychosis-proneness scores. The present results indicate that psychosis-proneness was associated with an increase in anxiety when individuals were with friends and an increase in depressed mood in daily task situations such as working or studying. By contrast, psychosis-proneness predicted a decrease in depressed and anxious moods in other situations when the individual was not likely to be confronted by social contact with less known individuals, and lower anxious and depressed moods when in secure environments (in one's own home, home of family or friends). The implications of these findings are discussed in terms of understanding the expression of psychosis vulnerability and the potential reinforcement of maladaptive social behavior through operant conditioning mechanisms.

[Validation of the French translation of Beck's Sociotropy-Autonomy Scale]. / Validation de la version française du questionnaire de Sociotropie-Autonomie de Beck et collègues.

OBJECTIVES: To validate the French version of the Sociotropy- Autonomy Scale (SAS) developed by Beck and others. The SAS is a self-questionnaire of 60 items divided into 2 dimensions measuring sociotropy and autonomy. METHOD: The SAS was completed by 1028 students, 140 of whom jointly completed Robins' Personal Style Inventory-Revised, and 75 of whom completed the SAS again 3 months later. RESULTS: The principal-axes factor analysis conducted on all 60 items yielded 2 distinct dimensions: sociotropy and autonomy. The factor analysis of each dimension led us to identify 6 subdimensions, just as in the original instrument. CONCLUSION: The French translation features satisfying psychometric and conceptual characteristics and allows these dimensions to be studied in a French sample. Results are discussed with regards to adequacy when compared with the original Beck's version.