John Witton

Systematic review of the Hawthorne effect: New concepts are needed to study research participation effects

Objectives This study aims to (1) elucidate whether the Hawthorne effect exists, (2) explore under what conditions, and (3) estimate the size of any such effect. Study Design and Setting This systematic review summarizes and evaluates the strength of available evidence on the Hawthorne effect. An inclusive definition of any form of research artifact on behavior using this label, and without cointerventions, was adopted. Results Nineteen purposively designed studies were included, providing quantitative data on the size of the effect in eight randomized controlled trials, five quasiexperimental studies, and six observational evaluations of reporting on ones behavior by answering questions or being directly observed and being aware of being studied. Although all but one study was undertaken within health sciences, study methods, contexts, and findings were highly heterogeneous. Most studies reported some evidence of an effect, although significant biases are judged likely because of the complexity of the evaluation object. Conclusion Consequences of research participation for behaviors being investigated do exist, although little can be securely known about the conditions under which they operate, their mechanisms of effects, or their magnitudes. New concepts are needed to guide empirical studies.

The Effects of Demand Characteristics on Research Participant Behaviours in Non-Laboratory Settings: A Systematic Review

Background The concept of demand characteristics, which involves research participants being aware of what the researcher is investigating, is well known and widely used within psychology, particularly in laboratory-based studies. Studies of this phenomenon may make a useful contribution to broader consideration of the effects of taking part in research on participant behaviour. This systematic review seeks to summarise data from studies of the effects of demand characteristics on participant behaviours in non-laboratory settings. Methodology/Principal Findings Electronic databases were searched to identify eligible studies. These had to be purposely designed to evaluate possible effects of demand characteristics on at least one behavioural outcome under the autonomous control of the participants and use longitudinal study designs. Only 7 studies were included, 6 providing observational data and 1 experimental study, with 5 studies involving examination of possible effects on health behaviours. Although studies provided some evidence of effects of demand characteristics on participant behaviour, heterogeneous operationalisation of the construct, the limited number of studies and poor quality of study designs made synthesis and interpretation of study findings challenging. Conclusions/Significance Although widely accepted as important in psychology, there have been few dedicated studies of the effects of demand characteristics on research participant behaviours outside laboratory settings. This body of literature does not currently contribute to the wider study of research participation effects. A systematic review of data from laboratory-based studies is needed, as are high-quality primary studies in non-laboratory settings. We suggest that unqualified use of the term demand characteristics should be abandoned.

Can Research Assessments Themselves Cause Bias in Behaviour Change Trials? A Systematic Review of Evidence from Solomon 4-Group Studies

Background The possible effects of research assessments on participant behaviour have attracted research interest, especially in studies with behavioural interventions and/or outcomes. Assessments may introduce bias in randomised controlled trials by altering receptivity to intervention in experimental groups and differentially impacting on the behaviour of control groups. In a Solomon 4-group design, participants are randomly allocated to one of four arms: (1) assessed experimental group; (2) unassessed experimental group (3) assessed control group; or (4) unassessed control group. This design provides a test of the internal validity of effect sizes obtained in conventional two-group trials by controlling for the effects of baseline assessment, and assessing interactions between the intervention and baseline assessment. The aim of this systematic review is to evaluate evidence from Solomon 4-group studies with behavioural outcomes that baseline research assessments themselves can introduce bias into trials. Methodology/Principal Findings Electronic databases were searched, supplemented by citation searching. Studies were eligible if they reported appropriately analysed results in peer-reviewed journals and used Solomon 4-group designs in non-laboratory settings with behavioural outcome measures and sample sizes of 20 per group or greater. Ten studies from a range of applied areas were included. There was inconsistent evidence of main effects of assessment, sparse evidence of interactions with behavioural interventions, and a lack of convincing data in relation to the research question for this review. Conclusions/Significance There were too few high quality completed studies to infer conclusively that biases stemming from baseline research assessments do or do not exist. There is, therefore a need for new rigorous Solomon 4-group studies that are purposively designed to evaluate the potential for research assessments to cause bias in behaviour change trials.

Factors associated with the prescribing of buprenorphine or methadone for treatment of opiate dependence

The study investigates patient preferences and beliefs and treatment program factors related to the decision to prescribe either buprenorphine or methadone to opiate-dependent patients. The sample (N = 192) was recruited from 10 addiction treatment services in London. Data were collected by means of a single structured interview conducted with patients commencing a treatment episode at the participating agencies. Data on patient demographics, beliefs, attitudes, and preferences were collected using a structured interview. Data regarding treatment goals and prescribed medication were collected from interviews with clinical staff. Oral methadone had a higher preference rating than buprenorphine. Clinical prescribing practices were influenced by patient preferences (both positive and negative), by prior treatment experiences, and by current treatment goals. Patient preferences and beliefs about opioid agonist medications served as an important influence upon clinical prescribing practices. The odds of being prescribed buprenorphine were three times greater among those patients who reported a preference for buprenorphine. The odds of receiving a prescription for methadone were about twice as great among those for whom methadone was the more preferred medication. Preferences were related to previous treatment experiences with these opioid agonists, and for patients in both groups, personal experience was the most important source of information about the treatment options. Buprenorphine was more likely to be prescribed for short-term detoxification and methadone for maintenance treatment.

Cannabis use in adolescents: the impact of risk and protective factors and social functioning

The study uses a school-based sample to test the social and familial risk and protective factors relating to cannabis use. Based on a self-completion survey of 2078 14-16-year-olds (mean age of 15 years) attending seven standard state-run secondary schools in south London, an assessment was made of rates and risk factors for cannabis use. Twenty-four per cent of the total sample had ever used cannabis, with 15% having done so in the month prior to assessment. In addition to greater likelihood of illicit drug use, lifetime cannabis users were less likely to spend time regularly with both their mothers and fathers, but more likely to spend free time with friends who smoked, drank alcohol and used illicit drugs, and with friends involved in criminal activities. Among those who had ever used cannabis, frequency of cannabis use was predicted (using linear regression) by two onset factors (earlier initiation of drinking and cannabis use were both linked to more frequent use) and two social factors (more time spent with drug-using friends and less time spent with the mother). Overall, the study showed that early onset, itself predicted by social networks, is linked to more frequent use of cannabis and that this appears to be sustained by less time spent with parents and more with drug-using peers.

Assessment and management of cannabis use disorders in primary care

#### Summary points About a third of adults in the UK have tried cannabis, and 2.5 million people, mostly 16-29 year olds, have used it in the past year.1 Although most people who smoke cannabis will develop neither severe mental health problems nor dependence, regular use of cannabis may be associated with a range of health, emotional, behavioural, social, and legal problems, particularly in young, pregnant, and severely mentally ill people.2 3 The past decade has seen a shift in available cannabis preparations from resinous “hash” to intensively grown high potency herbal preparations, often referred to as skunk, which now dominates the UK market.4 Compared with traditional cannabis preparations, skunk tends to have higher levels of tetrahydrocannabinol, the main psychoactive constituent of cannabis, and lower levels of the anxiolytic cannabinoid cannabidiol. In January 2009 cannabis was returned to its original class B classification (from class C) under the UK Misuse of Drugs Act. Despite high levels of use, only 6% of those seeking treatment for substance misuse in England cite cannabis as their …

Adolescent psychological health problems and delinquency among volatile substance users in a school sample in south London

The study assessed prevalence of volatile substance abuse (VSA), and its link to other forms of psychoactive substance use and to other problem behaviours among 14–15 year olds recruited from sixteen secondary schools in south-west London. Lifetime use of volatile substances was reported by 126 young people (6% of the sample) whose mean age of first use was 12.6 years. Using logistic regression analysis, lifetime use of volatile substances was found to be associated with more frequent cigarette smoking and more frequent drinking in the previous month, with higher levels of anxiety, greater involvement in delinquent acts, and lower levels of educational aspirations. Among volatile substance abusers, more frequent use was associated with higher levels of psychological distress and greater delinquent activity. Volatile substance abuse may be a marker for other forms of substance use and for other behaviour problems. This issue remains inadequately explored by researchers and clinicians.

From the deal to the needle: Drug purchasing and preparation among heroin users in drug treatment in South London

The article uses a semi-structured interview method to assess the acquisition, preparation and use of heroin in a cohort of 114 drug users in contact with treatment services in south-east London, and examines the impact of the increase in crack availability on heroin use and preparation in this population. Seventy-six participants reported using heroin on a daily basis, involving an average of 2.8 hits and using a mean of 0.75 g on each using day. Although almost all of the sample bought their own heroin, very few were confident of assessing its quality, and the mean estimated purity level of heroin bought was 22.7%. Similarly, most of the sample believed that the heroin purchased was adulterated and, although most believed that the heroin quality was evident during the preparation stage, relatively few would ask about quality at the point of purchase, and it is apparent that the beliefs held by much of the sample about drug purity issues did not impact upon their behaviour. Seventy individuals reported the joint use of heroin and cocaine with 41 of these reporting that they used heroin to come down from the high of crack, although 17 of them reported simultaneous administration (either combined in the syringe or on the foil). The variations in patterns of behaviour identified and the lack of awareness of risk reported would suggest that there are significant implications for the development of both the harm reduction strategies for multiple drug users and for the treatment services for whom complex multiple drug use is increasingly the norm.

Dual diagnosis screening : preliminary findings on the comparison of 50 clients attending community mental health services and 50 clients attending community substance misuse services

While dual diagnosis research has often focussed on substance misuse disorders among mental health clients, relatively little is known about comparable rates of dual diagnosis in community mental health and substance misuse settings because of, inter alia, limitations and lack of consistency in screening. In the current study clinicians administered a brief screening tool, which detects problematic alcohol, drug use, psychosis and common mental health symptoms, to 50 substance misuse and 50 mental health treatment attenders. Sixty-four per cent of the total sample screened positive for dual diagnosis (positive for any psychiatric disorder and either a drug or alcohol problem). Highest rates were observed in the alcohol sample (92.3%), followed by the drug sample (87.5%), and lowest in the community mental health (CMHT) sample (38%). Current depression and social phobia were most prevalent in alcohol clients compared to psychosis, mania and suicidal ideation in CMHT clients. Around one-third of CMHT clients reported using drugs (mainly cannabis) and around a fifth reported problematic alcohol use. The study demonstrates the feasibility of incorporating a dual diagnosis screen into routine clinical practice. The screen can be used in both mental health and substance misuse treatment settings, which are evidently managing complex client caseloads.

In celebration of sensible drinking

The concept of sensible drinking is not new and can be traced back to at least the 4th century BC. In the mid-to-late 1980s, United Kingdom policy converged on a safe limit of 21 units of alcohol per week for men and 14 units per week for women. These were adopted into ‘The Health of the Nation’ that established targets for the reduction of those drinking more than these limits. In 1995, the Department of Health published a report entitled ‘Sensible drinking’ that promoted a daily limit of 3–4 units for men and 2–3 units for women. Weekly and daily recommendations running in parallel have resulted in a confusing public health message. A decade later the ‘Health of the Nation’ targets have not been achieved: While the proportion of males drinking more than the weekly limits has remained the same around 28%, the percentage of women doing so has actually increased from 11% to 17%. Clearly the sensible drinking message is not working but currently there is nothing better to replace it.