How is data completeness defined?

Definition of the data completeness measure used by NBOCA in its reporting and in Trust Results

Data completeness is defined as the proportion of patients with complete data for the variables age, sex, ASA grade, pathological TNM stage (tumour, node, metastasis staging) and site of cancer. This is because these seven variables are used for risk-adjustment. Mode of admission and number of co-morbidities are also used in the risk-adjustment model but are collected from HES/PEDW data and so are not included in the assessment of data completeness. Data completeness is only assessed in patients who underwent major resection because only in these patients could all seven data items be expected to be complete.