Waiting list randomized controlled trial within a case-finding design: methodological considerations

Measuring and Reducing Chemical Spills by Students: A Randomized Controlled Trial of Providing Feedback

The ability to handle chemicals safely is a key aspect of the learning development of students studying chemistry; however, there have been no previously reported investigations of the quantity of chemicals spilled by students during lab experiments. Therefore, the first part of this article reports the assessment of the volume of chemicals spilled by year 1 undergraduate chemistry students (n = 64) at a U.K. university during an existing chemical analysis practical designed to develop volumetric handling skills. The experiment was carried out on paper liners, allowing the areas of students' spills to be visible and quantified using calibrated spill volumes of liquid to determine the resultant spill area. The volume spilled by the student group was ca. 1.2% of that handled; however, the amount spilled by individual students ranged widely, from ca. 0.02% to ca. 10% of the volume handled. A feedback tool has been developed to allow laboratory demonstrators to rapidly quantify chemical spillage by individual students. This tool also provides the demonstrators with a framework to communicate the potential safety significance of the volume of chemical a student has spilled. A randomized controlled trial (RCT) was carried out to examine the effect of providing feedback to students on their chemical spillage during a subsequent experiment. From a cohort of 185 year 1 undergraduate students, 150 consented to be randomized (81%), and data was collected for 144 students (96% of those randomized). A Hodges-Lehmann estimator for the median change in volume spilled during the second experiment due to providing feedback on spillage during first experiment was a 50% decrease in volume spilled (95% confidence range: 0 to 80% decrease, Mann-Whitney U test p = 0.05). The RCT was a waiting list trial, with all student receiving feedback either during or after the RCT, with blinded assessment by the demonstrators assessing volume spilled for the RCT.

Meaning and Purpose (MaP) therapy II: Feasibility and acceptability from a pilot study in advanced cancer

OBJECTIVE

Meaning and Purpose (MaP) therapy aims to enhance meaning-based coping through a life review that focuses on the value and worth of the person, key relationships, sources of fulfillment, roles, and future priorities in living life out fully. We sought to test the feasibility and acceptability of a six-session model of MaP therapy against a wait-list control cohort in a pilot study seeking effect sizes on measures of adaptation.

METHOD

We randomized patients with advanced cancer to MaP therapy or wait-list control, with measures administered at baseline and after 6-8 weeks. Wait-list patients could then crossover to receive therapy, with further measures collected postintervention. Adherence to the manualized model was sustained through weekly supervision and fidelity coding of recorded sessions. We used generalized estimating equations to control for baseline and any correlation of data.ResultFrom 134 eligible participants, 57 (43%) consented, and 40 of 45 (89%) offered therapy completed 6 sessions. Key barriers to consenting patients were poor health (15 refusers and 4 withdrawals) and death intervened in 6 participants. MaP therapy generated adequate effect sizes in posttraumatic growth (new possibilities, appreciation of life, and personal strength) and life attitudes (choices and goal seeking) to permit calculation of power for a formal randomized, controlled trial.Significance of resultsDelivery of this model of existentially oriented therapy is feasible and acceptable to patients. A properly powered randomized controlled trial is justified to examine the efficacy of this intervention.

Determining the optimal approach to identifying individuals with chronic obstructive pulmonary disease: The DOC study

RATIONALE, AIMS, AND OBJECTIVES

Early identification of chronic obstructive pulmonary disease (COPD) results in patients receiving appropriate management for their condition at an earlier stage in their disease. The determining the optimal approach to identifying individuals with chronic obstructive pulmonary disease (DOC) study was a case-finding study to enhance early identification of COPD in primary care, which evaluated the diagnostic accuracy of a series of simple lung function tests and symptom-based case-finding questionnaires.

METHODS

Current smokers aged 35 or more were invited to undertake a series of case-finding tools, which comprised lung function tests (specifically, spirometry, microspirometry, peak flow meter, and WheezoMeter) and several case-finding questionnaires. The effectiveness of these tests, individually or in combination, to identify small airways obstruction was evaluated against the gold standard of spirometry, with the quality of spirometry tests assessed by independent overreaders. The study was conducted with general practices in the Yorkshire and Humberside area, in the UK.

RESULTS

Six hundred eighty-one individuals met the inclusion criteria, with 444 participants completing their study appointments. A total of 216 (49%) with good-quality spirometry readings were included in the analysis. The most effective case-finding tools were found to be the peak flow meter alone, the peak flow meter plus WheezoMeter, and microspirometry alone. In addition to the main analysis, where the severity of airflow obstruction was based on fixed ratios and percent of predicted values, sensitivity analyses were conducted by using lower limit of normal values.

CONCLUSIONS

This research informs the choice of test for COPD identification; case-finding by use of the peak flow meter or microspirometer could be used routinely in primary care for suspected COPD patients. Only those testing positive to these tests would move on to full spirometry, thereby reducing unnecessary spirometric testing.

The impact of lung function case-finding tests on smoking behaviour: A nested randomised trial within a case-finding cohort

RATIONALE AIMS AND OBJECTIVES

Increasing awareness of people's lung health through the use of lung function tests or symptom-based questionnaires is a potential method to aid smoking cessation. We investigated the impact of case-finding lung function tests for chronic obstructive pulmonary disease on smoking behaviour.

METHODS

Our trial used a novel waiting list randomised controlled trial design, nested within a case-finding cohort study. The cohort comprised current smokers aged 35 years or more, from general practices in Yorkshire and Humberside, who were randomised to receive lung function tests (spirometry, microspirometry, peak flow meter measurement, and a WheezoMeter) and case-finding questionnaires either immediately ("tests now") or later ("waiting list" control). Outcome measures included self-reported smoking cessation and number of cigarettes smoked at follow-up (at 2, 3, or 6 months after randomisation, depending on study site), with 409 participants included in the primary analysis.

RESULTS

Six hundred seventy-four participants were randomised using stratified block randomisation to the 2 groups (340 to "tests now" and 334 to "waiting list"), with 409 included in the primary analysis (194 in "tests now" and 215 in "waiting list" groups). Smoking cessation at follow-up was very similar across groups (8.8% in the "tests now" group, compared with 9.2% in the "waiting list" group). Completing case-finding lung function tests did not significantly impact smoking cessation (OR 1.00, 95% CI, 0.57-1.77, adjusting for age, sex, baseline number of cigarettes smoked, and study site). A sensitivity analysis, assuming that participants with missing data were still smoking, gave similar results (OR 0.86, 95% CI, 0.47-1.56). Analysis of the number of cigarettes smoked at follow-up using negative binomial regression adjusting for the same factors above gave an incidence rate ratio of 0.95 (95% CI, 0.88-1.03).

CONCLUSIONS

There is no evidence from this trial of an effect of lung function tests on smoking cessation among a population of smokers aged 35 years or over. Indeed, when assuming that those with missing data were smokers, a slightly lower odds of smoking cessation was observed in the "test now" group compared with the "waiting list" group.

The power and value of placebo and nocebo in painful osteoarthritis

This paper reviews some recent advances in our understanding of the effects of sham or dummy interventions on pain and other symptoms in osteoarthritis (OA), and outlines two new approaches to the investigation of placebo and nocebo effects. We argue that the placebo effect provides us with a valuable way of investigating the nature of conditions like OA. For example, by examining which symptoms, biochemical markers or imaging features do or do not respond to placebo, we might learn more about the relationships between pathology and symptoms in OA. Placebo and nocebo effects are positive or negative outcomes resulting from the human interactions and contexts in which healthcare consultations take place. Subtle changes in behaviours and the environments in which consultations take place can have major effects on pain and other symptoms being experienced by people with OA. Nocebo effects are particularly powerful, leading to many health-care professionals (HCPs) causing unintended harm to their clients. Based on our own research, we conclude that beneficial outcomes are most likely to occur when both the (HCP) and the client feel safe and relaxed, and when the experiences of the client are validated by the (HCP). These findings have important implications for clinical practice. We believe that research in this field needs to be 'trans-disciplinary', escaping from the constraints of the purely biomedical, deterministic, positivist paradigm of most medical research. We provide the example of our own work which combines performance studies and scholarship, with psychology and medicine.

Electronic prompts significantly increase response rates to postal questionnaires: a randomized trial within a randomized trial and meta-analysis

OBJECTIVES

To assess the effectiveness of sending electronic prompts to randomized controlled trial participants to return study questionnaires.

STUDY DESIGN AND SETTING

A "trial within a trial" embedded within a study determining the effectiveness of chronic obstructive pulmonary disease (DOC) screening on smoking cessation. Those participants taking part in DOC who provided a mobile phone number and/or an electronic mail address were randomized to either receive an electronic prompt or no electronic prompt to return a study questionnaire. The results were combined with two previous studies in a meta-analysis.

RESULTS

A total of 437 participants were randomized: 226 to the electronic prompt group and 211 to the control group. A total of 285 (65.2%) participants returned the follow-up questionnaire: 157 (69.5%) in the electronic prompt group and 128 (60.7%) in the control group [difference 8.8%; 95% confidence interval (CI): -0.11%, 17.7%; P = 0.05]. The mean time to response was 23 days in the electronic prompt group and 33 days in the control group (hazard ratio = 1.27; 95% CI: 1.105, 1.47). The meta-analysis of all three studies showed an increase in response rate of 7.1% (95% CI: 0.8%, 13.3%).

CONCLUSION

The use of electronic prompts increased response rates and reduces the time to response.