Veronica Morton

Effect of regression to the mean on decision making in health care

Regression to the mean is a widespread statistical phenomenon with potentially serious implications for health care. It can result in wrongly concluding that an effect is due to treatment when it is due to chance. Ignorance of the problem will lead to errors in decision making. We discuss the importance of the issue and its effects on many common clinical, public health, and managerial decisions.

A Systematic Evaluation of the Impact of STRICTA and CONSORT Recommendations on Quality of Reporting for Acupuncture Trials

Background We investigated whether there had been an improvement in quality of reporting for randomised controlled trials of acupuncture since the publication of the STRICTA and CONSORT statements. We conducted a before-and-after study, comparing ratings for quality of reporting following the publication of both STRICTA and CONSORT recommendations. Methodology and Principal Findings Ninety peer reviewed journal articles reporting the results of acupuncture trials were selected at random from a wider sample frame of 266 papers. Papers published in three distinct time periods (1994–1995, 1999–2000 and 2004–2005) were compared. Assessment criteria were developed directly from CONSORT and STRICTA checklists. Papers were independently assessed for quality of reporting by two assessors, one of whom was blind to information which could have introduced systematic bias (e.g. date of publication). We detected a statistically significant increase in the reporting of CONSORT items for papers published in each time period measured. We did not, however, find a difference between the number of STRICTA items reported in journal articles published before and 3 to 4 years following the introduction of STRICTA recommendations. Conclusions and Significance The results of this study suggest that general standards of reporting for acupuncture trials have significantly improved since the introduction of the CONSORT statement in 1996, but that quality in reporting details specific to acupuncture interventions has yet to change following the more recent introduction of STRICTA recommendations. Wider targeting and revision of the guidelines is recommended.

Cost-effectiveness of shared pharmaceutical care for older patients: RESPECT trial findings

BACKGROUND Pharmaceutical care serves as a collaborative model for medication review. Its use is advocated for older patients, although its cost-effectiveness is unknown. Although the accompanying article on clinical effectiveness from the RESPECT (Randomised Evaluation of Shared Prescribing for Elderly people in the Community over Time) trial finds no statistically significant impact on prescribing for older patients undergoing pharmaceutical care, economic evaluations are based on an estimation, rather than hypothesis testing. AIM To evaluate the cost-effectiveness of pharmaceutical care for older people compared with usual care, according to National Institute for Health and Clinical Excellence (NICE) reference case standards. METHODS An economic evaluation was undertaken in which NICE reference case standards were applied to data collected in the RESPECT trial. RESULTS On average, pharmaceutical care is estimated to cost an incremental 10 000 UK pounds per additional quality-adjusted life year (QALY). If the NHSs cost-effectiveness threshold is between 20 000 and 30 000 UK pounds per extra QALY, then the results indicate that pharmaceutical care is cost-effective despite a lack of statistical significance to this effect. However, the statistical uncertainty surrounding the estimates implies that the probability that pharmaceutical care is not cost-effective lies between 0.22 and 0.19. Although results are not sensitive to assumptions about costs, they differ between subgroups: in patients aged >75 years pharmaceutical care appears more cost-effective for those who are younger or on fewer repeat medications. CONCLUSION Although pharmaceutical care is estimated to be cost-effective in the UK, the results are uncertain and further research into its long-term benefits may be worthwhile.

Shoulder acute pain in primary healthcare: is retraining effective for GP principals? SAPPHIRE—a randomized controlled trial

OBJECTIVE To address the question whether general practitioners (GPs) should receive practical training in shoulder problems and to test whether cortisone injections are better than anaesthetic injections for rotator cuff problems. METHODS A pragmatic split-plot, randomized trial with a cluster factorial design, conducted in general practices across five centres across the United Kingdom. Ninety-one practices were randomized to receive additional training in diagnosing and injecting rotator cuff problems or no additional training. Two hundred patients consulting their general practices with shoulder pain were then randomized to receive either a corticosteroid or lignocaine injection. The main outcome was score on the British Shoulder Disability Questionnaire (BSDQ). The Short-Form 36-item Health Survey and EuroQol at 12 months from entry to the trial were also scored. RESULTS Over the course of the trial there was a mean difference of 0.94 (s.e. = 1.01) on the BSDQ score between the groups, with patients treated by the untrained group having a mean of 9.46 (s.e. = 0.82) and those by the trained group having a mean of 8.51 (s.e. = 0.60). There were no statistically significant differences between the groups. Analysing by substance injected, there was a mean difference of 0.15 (s.e. = 0.48) throughout the trial between the groups, with patients given the cortisone having a mean BSDQ of 9.67 (s.e. = 0.39) and those given lignocaine, 9.82 (s.e. = 0.39). This was not statistically significantly different. CONCLUSIONS Training GPs in the diagnosis and treatment of shoulder disorders does not make any difference to the outcome, in terms of pain and disability, 1 yr later. Further, there is no advantage to injecting steroid in a group with predominant rotator cuff disorder. Trial registration. International Standard Randomized Controlled Trial Number 58537244. Trial steering committee comprised Prof. Paul Dieppe, Prof. Elaine Hay, Dr Brian Hazleman and Dr Kerenza Hood.

The effectiveness and cost-effectiveness of opportunistic screening and stepped care interventions for older hazardous alcohol users in primary care (AESOPS) – A randomised control trial protocol

BackgroundThere is a wealth of evidence regarding the detrimental impact of excessive alcohol consumption. In older populations excessive alcohol consumption is associated with increased risk of coronary heart disease, hypertension, stroke and a range of cancers. Alcohol consumption is also associated with an increased risk of falls, early onset of dementia and other cognitive deficits. Physiological changes that occur as part of the ageing process mean that older people experience alcohol related problems at lower consumption levels. There is a strong evidence base for the effectiveness of brief psychosocial interventions in reducing alcohol consumption in populations identified opportunistically in primary care settings. Stepped care interventions involve the delivery of more intensive interventions only to those in the population who fail to respond to less intensive interventions and provide a potentially resource efficient means of meeting the needs of this population.Methods/designThe study design is a pragmatic prospective multi-centre two arm randomised controlled trial. The primary hypothesis is that stepped care interventions for older hazardous alcohol users reduce alcohol consumption compared with a minimal intervention at 12 months post randomisation. Potential participants are identified using the AUDIT questionnaire. Eligible and consenting participants are randomised with equal probability to either a minimal intervention or a three step treatment approach. The step treatment approach incorporates as step 1 behavioural change counselling, step 2 three sessions of motivational enhancement therapy and step 3 referral to specialist services. The primary outcome is measured using average standard drinks per day and secondary outcome measures include the Drinking Problems Index, health related quality of life and health utility. The study incorporates a comprehensive economic analysis to assess the relative cost-effectiveness of the interventions.DiscussionThe paper presents a protocol for the first pragmatic randomised controlled trial evaluating the effectiveness and cost-effectiveness of stepped care interventions for older hazardous alcohol users in primary care.Trial registrationISRCTN52557360

Improving response rates using a monetary incentive for patient completion of questionnaires: an observational study

BackgroundPoor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires.MethodsWe recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires.ResultsThe response rate following reminders for the historical controls was 78.1% (82 of 105) compared with 88.0% (389 of 442) for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial – the extra cost per additional respondent was almost £50.ConclusionThe direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study.

The DAMASK trial protocol: a pragmatic randomised trial to evaluate whether GPs should have direct access to MRI for patients with suspected internal derangement of the knee

BackgroundThough new technologies like Magnetic Resonance Imaging (MRI) may be accurate, they often diffuse into practice before thorough assessment of their value in diagnosis and management, and of their effects on patient outcome and costs. MRI of the knee is a common investigation despite concern that it is not always appropriate. There is wide variation in general practitioners (GPs) access to, and use of MRI, and in the associated costs. The objective of this study was to resolve uncertainty whether GPs should refer patients with suspected internal derangement of the knee for MRI or to an orthopaedic specialist in secondary care.Methods/DesignThe design consisted of a pragmatic multi-centre randomised trial with two parallel groups and concomitant economic evaluation. Patients presenting in general practice with suspected internal derangement of the knee and for whom their GP was considering referral to an orthopaedic specialist in secondary care were eligible for inclusion. Within practices, GPs or practice nurses randomised eligible and consenting participants to the local radiology department for an MRI examination, or for consultation with an orthopaedic specialist. To ensure that the waiting time from GP consultation to orthopaedic appointment was similar for both trial arms, GPs made a provisional referral to orthopaedics when requesting the MRI examination. Thus we evaluated the more appropriate sequence of events independent of variations in waiting times. Follow up of participants was by postal questionnaires at six, twelve and 24 months after randomisation. This was to ensure that the evaluation covered all events up to and including arthroscopy.DiscussionThe DAMASK trial should make a major contribution to the development of evidence-based partnerships between primary and secondary care professionals and inform the debate when MRI should enter the diagnostic pathway.

Increasing response rates to postal questionnaires: a randomised trial of variations in design

Objectives: Low response rates to postal questionnaires can threaten the validity of studies by reducing the effective sample size and introducing bias. The identification of methods with which to optimise response rates could, therefore, improve the quality of studies. In an attempt to identify such methods, we undertook a randomised trial of two simple variations in questionnaire design. Methods: Using a 2 × 2 factorial design, we conducted a randomised trial to test two variations in questionnaire design; the questionnaires were printed on either single-sided or double-sided paper and had either a single- or multiple-booklet layout. Using equal random allocation, 3836 women were randomised to receive one of these questionnaires as part of a study investigating risk factors for osteoporotic fractures. Results: One thousand eight hundred and seventy questionnaires were returned, giving an overall response rate of 48.7%. There were no significant differences in the overall response to each of the four questionnaire designs. When the number of responders who completed at least 50% of each of the three sections was identified, it was found that single-booklet questionnaires had a better response than the multiple-booklet questionnaires and that single-sided questionnaires had a better response than double-sided questionnaires. However, these results were not significant at the 5% level. There were no significant differences in the response to questions on the odd (left-hand side) pages for the single- compared with the double-sided questionnaires. Conclusion: As the most cost-effective use of resources, we would advocate the use of double- rather than single-sided questionnaires, and use of a single- rather than multiple-booklet design.

Shoulder acute pain in primary health care: is retraining GPs effective? The SAPPHIRE randomized trial: a cost–effectiveness analysis

OBJECTIVES To assess the cost-effectiveness of providing practical training to general practitioners (GPs) in shoulder problems, and administering a local anaesthetic (lignocaine) vs steroidal (cortisone) injection. METHODS A cost-effectiveness analysis conducted alongside a cluster randomized trial with a factorial design, in general practices across five centres within the UK. A total of 155 participant GPs were randomized to receive training or no training with 200 participants randomized to either lignocaine or cortisone. Health care costs, quality-adjusted life years (QALYs) and incremental cost per QALY gained over 1 year estimated from a health system and a societal perspective were the main outcomes measured. RESULTS Over 1 year, training GPs costs on average an additional pound sterling 211 (95% credibility interval - pound sterling 237, pound sterling 661) than no training and produces higher mean QALYs (0.075; -0.004, 0.154) per patient, yielding an incremental cost-effectiveness ratio of pound sterling 2813 per QALY gained for trained GPs. Over the same period of 1 year, lignocaine costs an average of pound sterling 122 more (- pound sterling 232, pound sterling 476) than cortisone and produces virtually no differential gain in mean QALYs (0.001; -0.068, 0.070), yielding an incremental cost per QALY gained of pound sterling 122,000 for lignocaine compared with cortisone. Across a range of cost-effectiveness thresholds, cortisone is as cost effective to inject as lignocaine. The probability that training is cost effective is above 0.95 at thresholds above pound sterling 20,000. CONCLUSIONS Providing practical training to GPs about shoulder problems is cost effective and there is little uncertainty regarding this decision. The choice between lignocaine and cortisone is more uncertain and it is likely that there is significant value of further research to reduce this uncertainty. TRIAL REGISTRATION The International Standard Randomised Controlled Trial Number is 58 537 244.

Randomized controlled trial of a lay-facilitated angina management programme.

Aims This article reports a randomized controlled trial of lay-facilitated angina management (registered trial acronym: LAMP). Background Previously, a nurse-facilitated angina programme was shown to reduce angina while increasing physical activity, however most people with angina do not receive a cardiac rehabilitation or self-management programme. Lay people are increasingly being trained to facilitate self-management programmes. Design A randomized controlled trial comparing a lay-facilitated angina management programme with routine care from an angina nurse specialist. Methods Participants with new stable angina were randomized to the angina management programme (intervention: 70 participants) or advice from an angina nurse specialist (control: 72 participants). Primary outcome was angina frequency at 6 months; secondary outcomes at 3 and 6 months included: risk factors, physical functioning, anxiety, depression, angina misconceptions and cost utility. Follow-up was complete in March 2009. Analysis was by intention-to-treat; blind to group allocation. Results There was no important difference in angina frequency at 6 months. Secondary outcomes, assessed by either linear or logistic regression models, demonstrated important differences favouring the intervention group, at 3 months for: Anxiety, angina misconceptions and for exercise report; and at 6 months for: Anxiety; Depression; and angina misconceptions. The intervention was considered cost-effective. Conclusion The angina management programme produced some superior benefits when compared to advice from a specialist nurse.