PPH conditions are categorised as vaccine-preventable, acute or chronic, with the specific conditions classified as PPH varying across countries.
Self-reported co-morbidity, from a predetermined list of conditions, was categorised as painful or non-painful comorbidity.
For descriptive purpose, the frequency count on the number of conditions was categorised into three (2 5 conditions, 6 8 conditions and 9 or more) and in regression analyses, a continuous count on the number of conditions was used.
Across the three time-periods, there appeared to be a declining trend in the proportion of 'Circulatory system 'conditions and increasing proportions of 'Ill-defined conditions' and 'Respiratory system' conditions.> -wrap-foot> Conditions are categorised by ICD9 chapter heading descriptions.
Shape was categorised as roundish, oblong, fusiform or geographical.
In figures 14 and 15, genes which were differentially expressed between wild type and esk1-5 munder under the three conditions tested, were categorised according to their function, based on the Gene Ontologies (subsets of the GO: Biological process and Molecular function).
Comorbidities were classed in three different ways: i) The total number of comorbid conditions ('comorbidity count') was summed for each patient and categorised into four groups 0, 1, 2 or 3+ conditions; ii) Charlson comorbidity scores were categorised into 0, 1–2 or 3+; and iii) Specific comorbid conditions were individually categorised.
Following data extraction, systematic reviews identified were categorised by condition treated (asthma, COPD, bronchiectasis, interstitial lung disease, bronchitis, bronchoconstriction, pulmonary arterial hypertension, breathlessness (generic), and respiratory failure) and by treatment type (i.e. non-pharmacological/pharmacological).
Health conditions of participants in the trials were categorised using the broad categories of the International Classification of Diseases tenth edition (ICD-10).
