|Study||1 y||5 y|
|N*||Actual Confounding Factors Included in the Fully Adjusted Model||N*||Actual Confounding Factors Included in the Fully Adjusted Model|
|Oxford||1290||Age3†, NIHSS (2-term)†, prestroke mRS, and stroke type||732||Age3†, NIHSS (2-term)†, and prestroke mRS|
|Joinville||979||Age3†, NIHSS, and stroke type||…|
|Melbourne||975||Age, log NIHSS†, prestroke Barthel (2-term)†, AF, and stroke type||975||Age, log NIHSS†, prestroke Barthel (2-term)†, AF, and stroke type|
|Arcadia||547||Age, GCS, and AF||…|
|Perth||183||Age, NIHSS, prestroke mRS, and stroke type||…|
|Orebro||377||Age, log NIHSS†, institutional residence, and stroke type||377||Age3†, log NIHSS†, institutional residence, and stroke type|
|Dijon||3994||Age3†, LOC, AF, and smoking||3094||Age3†, LOC, AF, smoking, and stroke type|
|Martinique||569||Age3†, Barthel at onset (2-term)†, and history of PVD||569||Age3† and Barthel at onset (2-term)†|
|Porto||650||Age, LOC, smoking, and prestroke mRS||650||Age, LOC, and prestroke mRS3†|
|Auckland||1177||Age3†, log GCS†, prestroke dependence‡, AF, and stroke type||1177||Age3†, log GCS†, prestroke dependence‡, and AF|
|L’Aquila||3794||Age, LOC§, AF, hospital admission, stroke type, and smoking||3794||Age, LOC§, AF, hospital admission, and stroke type|
|Matão||79||Age§ and NIHSS||…|
|Tartu||358||Age and log NIHSS†||…|
|Total cases||14 972||11 368|
Of note, covariates were transformed, as necessary to get the best model fit. AF indicates atrial fibrillation; GCS, Glasgow Coma Scale; LOC, loss of consciousness; mRS, modified Rankin scale; NIHSS, National Institutes of Health Stroke Scale; and PVD, peripheral vascular disease.
↵* The sample size was the same among the unadjusted model and fully adjusted model.
↵† Transformations were based on the powers (eg, 3rd power and 2 power terms) suggested by fractional polynomials that produced the best-fitting multivariable model.
↵‡ Self-reported data about whether the patient lived independently before stroke.
↵§ Not meeting criteria of being a confounder but remain in the fully-adjusted multivariable model.