Bacchieri, 2010 [29]

Poisson regression

Rate ratio

Both

Robust standard errors

Timetoevent

No

Fixed effect (no interaction)

None

None

Minor

Bashour, 2013 [22]

Linear regression

Mean difference

Both

Random effects

No

Yes

Fixed effect

None

None

Major

(no interaction)

Durovni, 2013 [12]

Cox regression

Rate ratio

Withinstep only, plus frailty

Random effects

Timetoevent

Yes

Conditional

Major

None

Minor

Fuller, 2012 [23]

Logistic regression

Odds ratio

Both

Random effects

Yes, not explicitly accounted for

Yes

Fixed effects

Major

None (perprotocol analysis using observed lags)

Major

(no interaction)

Gruber 2013 [21]

Linear regression, LogPoisson regression

Risk difference, risk ratio

Both

Robust standard errors, GEE

Yes, not explicitly accounted for

Yes, in secondary analyses

Fixed effect

Major

None

Low

(no interaction)

Horner, 2012 [27]

Logistic regression

Odds ratio

Both

Random effects

Yes, not explicitly accounted for

Yes

Fixed effect

Minor

None

Minor

(no interaction)

Mhurchu, 2013 [24]

Logistic regression

Odds ratio

Both

Random effects

Yes, pupillevel summaries and random effect

Yes

Fixed effect

None

None

Minor

(no interaction)

Roy, 2013 [25]

Logistic regression

Odds ratio

Both

Random effects

No

Yes

None

None

None

Minor

Schultz, 2014 [28]

Logistic regression

Odds ratio

Both

None: GEE not possible, and RE did not converge

No

No

Fixed effect

Minor

None

None

(no interaction)

Stern, 2014 [26]

Linear regression

Mean difference

Both

Random effects

Yes, multiple level random effects

Yes

Fixed effect with interaction

Major

None

Minor
