Table 1

Quality Assessment Components and Ratings for EPHPP Instrument





Selection bias

Very likely to be representative of target population; greater than 80% participation rate

Somewhat likely to be representative of target population; 60-79% participation rate

All other responses or not stated


Randomized Control Trial, Clinical Control Trial

Cohort analytic, case-control, cohort, or interrupted time series

All other designs or design not stated


Controlled for at least 80% of confounders

Controlled for 60-79% of confounders

Confounders not controlled for, or not stated


Blinding of outcome assessor & participants to intervention &/or research question

Blinding of either outcome assessor or participants

Outcome assessor & participants are aware of intervention &/or research question

Data collection methods

Tools are valid & reliable

Tools are valid but reliability not described

No evidence of validity or reliability

Withdrawals & dropouts

Follow-up rate of > 80% of participants

Follow-up rate of 60-79% of participants

Follow-up rate of < 60% of participants or withdrawals & dropouts not described

Copyright 2004 by John Wiley and Sons. Adapted with permission of the author.

Cancelliere et al. BMC Public Health 2011 11:395   doi:10.1186/1471-2458-11-395

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