Biomarkers in osteoarthritis can be categorised using the burden of disease, investigative, prognostic, efficacy of intervention, diagnostic and safety classification.
Remoteness of residence when diagnosed with breast cancer will be categorised using the ARIA+ classification, which is a measure of accessibility and remoteness based on geographical location [ 59].
The European Germ Cell Cancer Consensus Group (EGCCCG) recommend that TNM staging be used [ 10] (Table 1) and that patients be categorised using the International Germ Cell Cancer Collaborative Group (IGCCCG) classification which stratifies patients into good, intermediate and poor prognostic groups.
BMI was categorised using the WHO categorisation (World Health Organization Consultation on Obesity, 1998): BMI <18.5 (underweight), 18.5 24.9 (normal), 25.0 29.9 (preobese/overweight) and ⩾30.0 (obese).
Body mass index was categorised using the WHO categorisation (World Health Organization Consultation on Obesity, 1998): BMI <18.5 (underweight), 18.5 24.9 (normal), 25.0 29.9 (preobese/overweight) and ≥30.0 kg/m (obese).
This index will be categorised using a median split to determine if the food environment is 'healthy' (<50th centile of unhealthy food outlets/healthy food outlets) or 'unhealthy' (≥50th centile of unhealthy food outlets/healthy food outlets).
Among the approximately 800 000 cases at our hospital, 8772 were categorised using the terms 'Inclusion criteria: Osteoporosis diagnosis'; among this group, 7195 were further categorised using 'Inclusion criteria: Osteoporosis drug administration'.
There are a number of possible causes of wildlife decline, which can be categorised using Diamond's 'evil quartet' of factors driving species extinctions.
Pathologies were categorised using the diagram shown in Fig. 1 [6].
Toxicity was categorised using the National Cancer Institute Common Toxicity Criteria (version 2.0).
