RCT

Q‐RCT

NRCT

CBA

PCS

RCS

HCT

NCC

CC

XS

BA

CR/CS

Was there a comparison:

Between two or more groups of participants receiving different interventions?

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

N

N

Within the same group of participants over time?

P

P

N

Y

N

N

N

N

N

N

Y

N

Were participants allocated to groups by:

Concealed randomization?

Y

N

N

N

N

N

N

N

N

N

na

na

Quasi‐randomization?

N

Y

N

N

N

N

N

N

N

N

na

na

By other action of researchers?

N

N

Y

P

N

N

N

N

N

N

na

na

Time differences?

N

N

N

N

N

N

Y

N

N

N

na

na

Location differences?

N

N

P

P

P

P

P

na

na

na

na

na

Treatment decisions?

N

N

N

P

P

P

N

N

N

P

na

na

Participants' preferences?

N

N

N

P

P

P

N

N

N

P

na

na

On the basis of outcome?

N

N

N

N

N

N

N

Y

Y

P

na

na

Some other process? (specify)

Which parts of the study were prospective:

Identification of participants?

Y

Y

Y

P

Y

N

P*

Y

N

N

P

P

Assessment of baseline and allocation to intervention?

Y

Y

Y

P

Y

N

P*

Y

N

N

na

na

Assessment of outcomes?

Y

Y

Y

P

Y

P

P

Y

N

N

P

P

Generation of hypotheses?

Y

Y

Y

Y

Y

Y

Y

Y

P

P

P

na

On what variables was comparability between groups assessed:

Potential confounders?

P

P

P

P

P

P

P

P

P

P

N

na

Baseline assessment of outcome variables?

P

P

P

Y

P

P

P

N

N

N

N

na