[The quality of cancer registry. From a methodology approach].

Since 1996 at the unit of epidemiological research of the "Hospital de Pediatría en Centro Medico Nacional Siglo XXI" a cancer registry in children has been done. This registry has been a pioneer with special features like be only in child population attended in Mexico City. The following paper describes the main characteristics of the registry, the strategy used to obtain the data, the quality criterion applied for selecting data like timeliness, validated and complete. A longitudinal and prolective data was obtained. There was a training period for obtaining and register the data. The data was obtained from children with neoplasm attended at the mentioned hospital above. The diagnosis of a solid neoplasm was established by histology and marrow aspirated studies. The population studied was children (0-14 years). It was calculated the incidence (per 1000 000 children/year) by age, sex, diagnosis and place of residence. The trend was evaluated by estimating the average annual percent of change.