Zarnie Khadjesari

Can stand-alone computer-based interventions reduce alcohol consumption? A systematic review

AIM To determine the effects of computer-based interventions aimed at reducing alcohol consumption in adult populations. METHODS The review was undertaken following standard Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance for systematic reviews. The literature was searched until December 2008, with no restrictions on language. Randomized trials with parallel comparator groups were identified in the form of published and unpublished data. Two authors independently screened abstracts and papers for inclusion. Data extraction and bias assessment was undertaken by one author and checked by a second author. Studies that measured total alcohol consumption and frequency of binge drinking episodes were eligible for inclusion in meta-analyses. A random-effects model was used to pool mean differences. RESULTS Twenty-four studies were included in the review (19 combined in meta-analyses). The meta-analyses suggested that computer-based interventions were more effective than minimally active comparator groups (e.g. assessment-only) at reducing alcohol consumed per week in student and non-student populations. However, most studies used the mean to summarize skewed data, which could be misleading in small samples. A sensitivity analysis of those studies that used suitable measures of central tendency found that there was no difference between intervention and minimally active comparator groups in alcohol consumed per week by students. Few studies investigated non-student populations or compared interventions with active comparator groups. CONCLUSION Computer-based interventions may reduce alcohol consumption compared with assessment-only; the conclusion remains tentative because of methodological weaknesses in the studies. Future research should consider that the distribution of alcohol consumption data is likely to be skewed and that appropriate measures of central tendency are reported.

Methodological Challenges in Online Trials

Health care and health care services are increasingly being delivered over the Internet. There is a strong argument that interventions delivered online should also be evaluated online to maximize the trial’s external validity. Conducting a trial online can help reduce research costs and improve some aspects of internal validity. To date, there are relatively few trials of health interventions that have been conducted entirely online. In this paper we describe the major methodological issues that arise in trials (recruitment, randomization, fidelity of the intervention, retention, and data quality), consider how the online context affects these issues, and use our experience of one online trial evaluating an intervention to help hazardous drinkers drink less (DownYourDrink) to illustrate potential solutions. Further work is needed to develop online trial methodology.

On-line Randomized Controlled Trial of an Internet Based Psychologically Enhanced Intervention for People with Hazardous Alcohol Consumption

Background Interventions delivered via the Internet have the potential to address the problem of hazardous alcohol consumption at minimal incremental cost, with potentially major public health implications. It was hypothesised that providing access to a psychologically enhanced website would result in greater reductions in drinking and related problems than giving access to a typical alcohol website simply providing information on potential harms of alcohol. DYD-RCT Trial registration: ISRCTN 31070347. Methodology/Principal Findings A two-arm randomised controlled trial was conducted entirely on-line through the Down Your Drink (DYD) website. A total of 7935 individuals who screened positive for hazardous alcohol consumption were recruited and randomized. At entry to the trial, the geometric mean reported past week alcohol consumption was 46.0 (SD 31.2) units. Consumption levels reduced substantially in both groups at the principal 3 month assessment point to an average of 26.0 (SD 22.3) units. Similar changes were reported at 1 month and 12 months. There were no significant differences between the groups for either alcohol consumption at 3 months (intervention: control ratio of geometric means 1.03, 95% CI 0.97 to 1.10) or for this outcome and the main secondary outcomes at any of the assessments. The results were not materially changed following imputation of missing values, nor was there any evidence that the impact of the intervention varied with baseline measures or level of exposure to the intervention. Conclusions/Significance Findings did not provide support for the hypothesis that access to a psychologically enhanced website confers additional benefit over standard practice and indicate the need for further research to optimise the effectiveness of Internet-based behavioural interventions. The trial demonstrates a widespread and potentially sustainable demand for Internet based interventions for people with hazardous alcohol consumption, which could be delivered internationally. Trial Registration Controlled-Trials.com ISRCTN31070347

Impact and costs of incentives to reduce attrition in online trials: two randomized controlled trials.

Background Attrition from follow-up is a major methodological challenge in randomized trials. Incentives are known to improve response rates in cross-sectional postal and online surveys, yet few studies have investigated whether they can reduce attrition from follow-up in online trials, which are particularly vulnerable to low follow-up rates. Objectives Our objective was to determine the impact of incentives on follow-up rates in an online trial. Methods Two randomized controlled trials were embedded in a large online trial of a Web-based intervention to reduce alcohol consumption (the Down Your Drink randomized controlled trial, DYD-RCT). Participants were those in the DYD pilot trial eligible for 3-month follow-up (study 1) and those eligible for 12-month follow-up in the DYD main trial (study 2). Participants in both studies were randomly allocated to receive an offer of an incentive or to receive no offer of an incentive. In study 1, participants in the incentive arm were randomly offered a £5 Amazon.co.uk gift voucher, a £5 charity donation to Cancer Research UK, or entry in a prize draw for £250. In study 2, participants in the incentive arm were offered a £10 Amazon.co.uk gift voucher. The primary outcome was the proportion of participants who completed follow-up questionnaires in the incentive arm(s) compared with the no incentive arm. Results In study 1 (n = 1226), there was no significant difference in response rates between those participants offered an incentive (175/615, 29%) and those with no offer (162/611, 27%) (difference = 2%, 95% confidence interval [CI] –3% to 7%). There was no significant difference in response rates among the three different incentives offered. In study 2 (n = 2591), response rates were 9% higher in the group offered an incentive (476/1296, 37%) than in the group not offered an incentive (364/1295, 28%) (difference = 9%, 95% CI 5% to 12%, P < .001). The incremental cost per extra successful follow-up in the incentive arm was £110 in study 1 and £52 in study 2. Conclusion Whereas an offer of a £10 Amazon.co.uk gift voucher can increase follow-up rates in online trials, an offer of a lower incentive may not. The marginal costs involved require careful consideration. Trial registration ISRCTN31070347; http://www.controlled-trials.com/ISRCTN31070347 (Archived by WebCite at http://www.webcitation.org/5wgr5pl3s)

Development of a psychologically enhanced interactive online intervention for hazardous drinking

Aims: The content of novel interventions is often not well specified. We provide a detailed account of the rationale for and redevelopment of an Internet resource for hazardous drinkers—Down Your Drink (DYD) (www.downyourdrink.org.uk). Development Work: An iterative process blended literature reviews of Internet interventions for health conditions and brief treatments for alcohol problems, feedback from users of the original site and from users panels, and completion of a series of developmental tasks. Intervention: The detailed structure and content of the new version of the website is presented. This permits an appreciation of the intended interaction between the user and the intervention, and emphasizes both the freedom of choice available to the user to access diverse material for personal benefit and the value of a clear organizational structure. Conclusions: Presentation of detailed information on the theoretical underpinning, content and structure of an intervention makes it easier to interpret the results of any evaluation and is likely to be of use to those developing other online interventions for alcohol or other health behaviours.

Impact of NICE guidance on laparoscopic surgery for inguinal hernias: analysis of interrupted time series

After the introduction of Bassinis procedure in the late 19th century, methods of repairing hernias changed little until the 1990s, when synthetic mesh and laparoscopic methods arrived.1 In contrast to the open mesh technique, laparoscopic surgery remains uncommon. In January 2001, the National Institute for Clinical Excellence (NICE) issued guidance that stated, “For repair of primary inguinal hernia, open [mesh] should be the preferred surgical procedure.”2 We describe patterns of surgical repair of inguinal hernias and assess the impact of NICEs guidance. We found 217 000 cases with a primary procedure code for primary surgery for an inguinal hernia from the hospital episode statistics database for England from April 1998 to December 2001. Of these, secondary procedure codes for minimal access surgery identified 8960 (4.1%) cases in which surgery was laparoscopic. We …

The DYD-RCT protocol: an on-line randomised controlled trial of an interactive computer-based intervention compared with a standard information website to reduce alcohol consumption among hazardous drinkers.

BackgroundExcessive alcohol consumption is a significant public health problem throughout the world. Although there are a range of effective interventions to help heavy drinkers reduce their alcohol consumption, these have little proven population-level impact. Researchers internationally are looking at the potential of Internet interventions in this area.Methods/DesignIn a two-arm randomised controlled trial, an on-line psychologically enhanced interactive computer-based intervention is compared with a flat, text-based information web-site. Recruitment, consent, randomisation and data collection are all on-line. The primary outcome is total past-week alcohol consumption; secondary outcomes include hazardous or harmful drinking, dependence, harm caused by alcohol, and mental health. A health economic analysis is included.DiscussionThis trial will provide information on the effectiveness and cost-effectiveness of an on-line intervention to help heavy drinkers drink less.Trial registrationInternational Standard Randomised Controlled Trial Number Register ISRCTN31070347

Attrition Revisited: Adherence and Retention in a Web-Based Alcohol Trial

Background Attrition is a noted feature of eHealth interventions and trials. In 2005, Eysenbach published a landmark paper calling for a “science of attrition,” suggesting that the 2 forms of attrition—nonusage attrition (low adherence to the intervention) and dropout attrition (poor retention to follow-up)—may be related and that this potential relationship deserved further study. Objective The aim of this paper was to use data from an online alcohol trial to explore Eysenbach’s hypothesis, and to answer 3 research questions: (1) Are adherence and retention related? If so, how, and under which circumstances? (2) Do adherence and retention have similar predictors? Can these predictors adequately explain any relationship between adherence and retention or are there additional, unmeasured predictors impacting on the relationship? (3) If there are additional unmeasured predictors impacting on the relationship, are there data to support Eysenbach’s hypothesis that these are related to overall levels of interest? Methods Secondary analysis of data from an online trial of an online intervention to reduce alcohol consumption among heavy drinkers. The 2 outcomes were adherence to the intervention measured by number of log-ins, and retention to the trial measured by provision of follow-up data at 3 months (the primary outcome point). Dependent variables were demographic and alcohol-related data collected at baseline. Predictors of adherence and retention were modeled using logistic regression models. Results Data were available on 7932 participants. Adherence and retention were related in a complex fashion. Participants in the intervention group were more likely than those in the control group to log in more than once (42% vs 28%, P<.001) and less likely than those in the control group to respond at 3 months (40% vs 49%, P<.001). Within each randomized group, participants who logged in more frequently were more likely to respond than those who logged in less frequently. Response rates in the intervention group for those who logged in once, twice, or ≥3 times were 34%, 46%, and 51%, respectively (P<.001); response rates in the control group for those who logged in once, twice, or ≥3 times were 44%, 60%, and 67%, respectively (P<.001). Relationships between baseline characteristics and adherence and retention were also complex. Where demographic characteristics predicted adherence, they tended also to predict retention. However, characteristics related to alcohol consumption and intention or confidence in reducing alcohol consumption tended to have opposite effects on adherence and retention, with factors that predicted improved adherence tending to predict reduced retention. The complexity of these relationships suggested the existence of an unmeasured confounder. Conclusions In this dataset, adherence and retention were related in a complex fashion. We propose a possible explanatory model for these data. Trial Registration International Standard Randomized Controlled Trial Number (ISRCTN): 31070347; http://www.controlled-trials.com/ISRCTN31070347 (Archived by WebCite at http://www.webcitation.org/6IEmNnlCn).

Impact of Length or Relevance of Questionnaires on Attrition in Online Trials: Randomized Controlled Trial

Background There has been limited study of factors influencing response rates and attrition in online research. Online experiments were nested within the pilot (study 1, n = 3780) and main trial (study 2, n = 2667) phases of an evaluation of a Web-based intervention for hazardous drinkers: the Down Your Drink randomized controlled trial (DYD-RCT). Objectives The objective was to determine whether differences in the length and relevance of questionnaires can impact upon loss to follow-up in online trials. Methods A randomized controlled trial design was used. All participants who consented to enter DYD-RCT and completed the primary outcome questionnaires were randomized to complete one of four secondary outcome questionnaires at baseline and at follow-up. These questionnaires varied in length (additional 23 or 34 versus 10 items) and relevance (alcohol problems versus mental health). The outcome measure was the proportion of participants who completed follow-up at each of two follow-up intervals: study 1 after 1 and 3 months and study 2 after 3 and 12 months. Results At all four follow-up intervals there were no significant effects of additional questionnaire length on follow-up. Randomization to the less relevant questionnaire resulted in significantly lower rates of follow-up in two of the four assessments made (absolute difference of 4%, 95% confidence interval [CI] 0%-8%, in both study 1 after 1 month and in study 2 after 12 months). A post hoc pooled analysis across all four follow-up intervals found this effect of marginal statistical significance (unadjusted difference, 3%, range 1%-5%, P = .01; difference adjusted for prespecified covariates, 3%, range 0%-5%, P = .05). Conclusions Apparently minor differences in study design decisions may have a measurable impact on attrition in trials. Further investigation is warranted of the impact of the relevance of outcome measures on follow-up rates and, more broadly, of the consequences of what we ask participants to do when we invite them to take part in research studies. Trial registration ISRCTN Register 31070347; http://www.controlled-trials.com/ISRCTN31070347/31070347 Archived by WebCite at (http://www.webcitation.org/62cpeyYaY)

Test-retest reliability of an online measure of past week alcohol consumption (the TOT-AL), and comparison with face-to-face interview

OBJECTIVE This paper reports on the development of a new online measure of beverage-specific past week alcohol consumption (the TOT-AL), its test-retest reliability, and comparability with the face-to-face approach of ascertaining alcohol intake. METHODS University students participating in the reliability study completed the TOT-AL twice on the same day with at least 3 h apart. Students in the comparability study attended a face-to-face interview and completed the TOT-AL on the same day, in a randomised order, at least 3 h apart. RESULTS There was a strong correlation between the repeated measurements of the TOT-AL (r=0.99; 95% CI: 0.98, 0.99) and between the units calculated by the TOT-AL and the face-to face interview (r=0.97; 95% CI: 0.95, 0.99). A high level of agreement between measurements was also observed in a Bland-Altman analysis. CONCLUSIONS The TOT-AL is a reliable, time efficient means of ascertaining alcohol intake, equivalent to that obtained face-to-face. These findings support the use of this approach to online alcohol assessment in populations with access to the Internet.