How usual is usual care in Chronic Obstructive Pulmonary Disease trials? A systematic review on quality of reporting and validity of comparator interventions

'Usual care' is a term that can refer to a variety of control conditions in randomized controlled trials (RCTs). The lack of standardization of usual care groups can lead to problems for clinical decision-making.

1) Systematically describe the types and characterizations of "usual care" interventions in COPD RCTs. 2) Determine how well RCTs report usual care interventions and the extent to which COPD guideline-recommended treatment components are a part of usual care interventions.

Systematic review design. Two investigators screened studies and independently extracted data. We extracted type of usual care described, quality of reporting, and classification of usual care components as validated (i.e., aligned with guidelines) or unvalidated comparators.

We included 233 studies. The most frequently described usual care intervention included patient education (n = 72, 31%) and continued care with the general practitioner (n = 67, 29%). Only 7% of the studies provided a complete description of the usual care intervention. Almost half of usual care interventions (49%) were deemed unvalidated. Higher PEDro scores were associated with greater odds of the intervention being validated (Exp(B) = 1.32; 95% CI: 1.04 to 1.66).

There is significant variability and frequent lack of reporting in the characterization of 'usual care' comparators in RCTs involving patients with COPD. Usual care is often poorly described, inconsistently delivered, and commonly not aligned with clinical guidelines. Higher quality trials had better odds of providing valid usual care.