Table 3

Estimates for sample size evaluation

Expected number
ReferenceCoding system usedAge, yearsNumber of chronic conditionsNumber of patientsPercentageSample size of 500Sample size of 750Sample size of 1000
Barnett et al, 20122Read codesNo age limit399 4870.418209314418
460 4170.254127190254
535 6410.15075112150
620 5070.086436586
711 0800.047233547
≥810 8460.046233446
Rizza et al, 201240ICPC-2≥20323190.48240360480
>325130.52260187520
Glynn et al, 20115ICPC-2>5036360.47233349466
43670.27134202269
≥53620.27133199265
  • ICPC-2, International Classification of Primary Care, V.2.