Study characteristics.

B-NMDS  =  Belgium Nursing Minimal Data Set, BMI  =  Body Mass Index, CCI  =  Charlson Comorbidity Index, CMG = Case Mix Group, CMI  =  Case Mix Index, DRG  =  Diagnose Resource Group, GRASP  =  Grace Reynolds Application and Study of PETO, LOS  =  Length of Stay, NANDA =  North American Nursing Diagnosis Association, NA  =  not applicable, NS  =  not significant, OPC  =  Oulu Patient Classification, OR  =  Odds Ratio, PAS  =  Patient Acuity Scale, PAONCIL  =  Professional Assessment of Optimal Nursing Care Intensity Level, PRN  =  Project Resource Nursing, Prinqual 1  =  self-care (dependency level), PSI  =  Patient Severity Index, RC  =  reference category, RNEUSI  =  Registered nurse equivalents Units of Service index, RVU  =  relative value unit, SENIC  =  Study of the Efficacy of Nosocomial Infection Control, SII  =  Horn's Severity of Illness index, SJ = San Joaquin