Power Estimation and Follow-Up Period Evaluation in Korea Radiation Effect and Epidemiology Cohort Study / 예방의학회지
Journal of Preventive Medicine and Public Health
;
: 543-548, 2010.
Artículo
en Coreano
| WPRIM
| ID: wpr-103483
ABSTRACT
OBJECTIVES:
The objective of this study was to calculate sample size and power in an ongoing cohort, Korea radiation effect and epidemiology cohort (KREEC).METHOD:
Sample size calculation was performed using PASS 2002 based on Cox regression and Poisson regression models. Person-year was calculated by using data from '1993-1997 Total cancer incidence by sex and age, Seoul' and Korean statistical informative service.RESULTS:
With the assumption of relative risk=1.3, exposurenon-exposure=12 and power=0.8, sample size calculation was 405 events based on a Cox regression model. When the relative risk was assumed to be 1.5 then number of events was 170. Based on a Poisson regression model, relative risk=1.3, exposurenon-exposure=12 and power=0.8 rendered 385 events. Relative risk of 1.5 resulted in a total of 157 events. We calculated person-years (PY) with event numbers and cancer incidence rate in the non-exposure group. Based on a Cox regression model, with relative risk=1.3, exposurenon-exposure=12 and power=0.8, 136 245PY was needed to secure the power. In a Poisson regression model, with relative risk=1.3, exposurenon-exposure=12 and power=0.8, person-year needed was 129517PY. A total of 1939 cases were identified in KREEC until December 2007.CONCLUSIONS:
A retrospective power calculation in an ongoing study might be biased by the data. Prospective power calculation should be carried out based on various assumptions prior to the study.
Texto completo:
Disponible
Índice:
WPRIM (Pacífico Occidental)
Asunto principal:
Riesgo
/
Incidencia
/
Estudios de Cohortes
/
Relación Dosis-Respuesta en la Radiación
/
República de Corea
/
Neoplasias Inducidas por Radiación
Tipo de estudio:
Estudio de etiología
/
Estudio de incidencia
/
Estudio observacional
/
Estudio pronóstico
/
Factores de riesgo
/
Estudio de tamizaje
Límite:
Adolescente
/
Adulto
/
Anciano
/
Aged80
/
Niño
/
Child, preschool
/
Femenino
/
Humanos
/
Lactante
/
Masculino
País/Región como asunto:
Asia
Idioma:
Coreano
Revista:
Journal of Preventive Medicine and Public Health
Año:
2010
Tipo del documento:
Artículo
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