Randomised study of n of 1 trials versus standard practice

Abstract

18 Brandenburg NA, Friedman RM, Silver SE. The epidemiology of childhood psychiatric disorders: prevalence findings from recent studies. JAm Acad ChildAdolesc Psychiatry 1990;29:76-83. Abstract Objective-To compare outcomes between groups of patients with irreversible chronic airflow limitation given theophylline by n of 1 trials or standard practice.Design-Randomised controlled study of n of 1 trials versus standard practice.Setting-Tertiary care centre outpatient department.Subjects-31 patients with irreversible chronic airflow limitation who were unsure that theophylline was helpful after an open trial.Interventions-n Of 1 trials (single patient randomised multiple crossover comparisons of theophylline against placebo) followed published guidelines. For standard practice patients theophylline was stopped and resumed if their dyspnoea worsened; if their dyspnoea then improved theophylline was continued. For both groups a decision to continue or stop the drug was made within three months of randomisation.Main outcome measures-Exercise capacity as measured by six minute walking distance, quality oflife as measured by the chronic respiratory disease questionnaire at baseline and six months after randomisation, and proportions of patients taking theophylline at six months. Results-26 patients completed follow up. 47% fewer n of 1 trial patients than standard practice patients were taking theophylline at six months (5114 versus 10/12; 95% confidence interval of difference 14% to 80%) without differences in exercise capacity or quality oflife.

Outcomes for patients with the same disease treated inside and outside of randomized trials: a systematic review and meta-analysis

“…38,41,86,87,141 In the remaining 142 studies, patients became part of the "outsiders" group for a variety of reasons. Table 2 presents the details about each included study.…”

The assessment of health status among patients with COPD

“…This instrument has been demonstrated to be more sensitive to change than generic health-status instruments, such as the NHP and the SIP [29,46]. The CRQ has been used to assess the effects of bronchodilators [71,75,76] and to make comparisons between bronchodilators or aerosol delivery mechanisms [45], modes of ventilation [77], long-term oxygen therapy [78] and pulmonary rehabilitation [73,[79][80][81][82][83][84][85]. It has been translated into many languages including Dutch [86], Spanish [25,87] and German [88].…”

A new generation of pragmatic trials of psychosocial interventions is needed

“…Specific dimensions of complexity are implicated in both the development and evaluation phases of research, such as: the ways in which a given intervention leads to change, lack of impact due to implementation failure and variability in individual-level outcomes, use of multiple primary outcomes and adaptation of intervention programmes to local settings (Craig et al 2008). In fact, conventional RCTs may be inapplicable in these instances, and assessment of treatment effectiveness may require solutions involving special experimental designs, such as cluster randomized trials (Barbui & Cipriani, 2011;Campbell et al 2012), stepped wedge designs (Hussey & Hughes, 2007), preference trials (Torgerson & Sibbald, 1998), randomized consent designs (Zelen, 2006) and 'N of 1 designs' (Mahon et al 1996). Furthermore, randomization may not always be necessary or appropriate, thus leaving a non-randomized design as the only choice (Mohr et al 2009;Catts et al 2010).…”