Table 2

Indicators of study quality
Quality indicator Uppal, 2003[19]; Uppal, 2004[20] Sittitavornwong, 2005[21] Susarla, 2011[22] Mandal, 2004[23]
Was the objective of the study clearly described? Yes Yes Yes Yes
Are the main outcomes to be measured clearly described? Yes Yes Yes Yes
Are the characteristics of the included subjects clearly described? Yes No Partial No
Was there a clearly defined point in time when the intervention occurred? Yes Yes Yes No
Are the interventions of interest clearly described? Yes No Yes Yes
Are possible confounders clearly described? Partial Partial Partial No
Are the main findings of the study clearly described? Yes Yes Yes Yes
Are estimates of the random variability in the data provided? Yes Yes Yes No
Are all adverse events that may be a consequence of the intervention reported? Unclear Unclear Unclear Unclear
Are the characteristics of patients lost to follow-up described? NA Yes NA No
Were losses of patients to follow up accounted for? NA Yes NA No
Are the actual probability values reported for the main outcomes? Yes No Yes No
Were attempts made to blind outcome assessors to the intervention? NA No NA NA
Were the groups recruited from the same population? No Yes Yes Yes
Were the groups recruited over the same period of time? No Yes Yes Unclear
Was a representative sample of the population approached? Yes Yes Unclear Unclear
Was the intervention unlikely to affect data collection? Yes Yes Yes Yes
Was there reliable compliance with the intervention? Partial Yes NA Yes
Were the main outcome measures used valid and reliable? Yes Yes Yes No
Was the study free from selective outcome reporting? Unclear Unclear Unclear Unclear
Were baseline characteristics similar between groups? Unclear Unclear Unclear Unclear

Thompson-Coon et al.

Thompson-Coon et al. BMC Health Services Research 2013 13:128   doi:10.1186/1472-6963-13-128

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