Table 1.
Summary characteristics of studies (N = 59)
| Study characteristic | Articles n (%) |
|---|---|
| Type of study (N = 59) | |
| Cross-sectional | 32 (54%) |
| Cohort/longitudinal | 26 (44%) |
| Case-control | 1 (2%) |
| World Bank classification (n = 59) | |
| High-income country | 56 (95%) |
| Middle-income country | 3 (5%) |
| Low-income country | 0 (0) |
| Source of data (n = 59)* | |
| Insurance claim database | 37 (63%) |
| Hospital/medical database | 19 (32%) |
| Patient survey | 20 (34%) |
| Linked database | 20 (34%) |
| Other | 6 (10%) |
| Type of costs included (n = 59)* | |
| Direct medical costs | 58 (98%) |
| Direct non-medical costs | 2 (3%) |
| Indirect costs | 7 (12%) |
| Costing perspective (n = 59)* | |
| Public | 48 (81%) |
| Household/patient | 12 (20%) |
| Societal | 8 (14%) |
| Provider | 1 (2%) |
| Number of disease combination sets from all studies* (n = 325) | |
| Included in narrative synthesis (research questions 1 and 4) | 229 (70%) |
| Included in country comparison (research question 2) | 41 (13%) |
| Included in meta-analyses (research question 3) | 34 (10%) |
| Number of conditions in each disease combination set (n = 325) | |
| Two | 282 (87%) |
| More than two | 43 (13%) |
| Frequently appeared in disease combination sets* (n = 325) | |
| Diabetes | 96 (30%) |
| Heart/vascular conditions | 93 (29%) |
| Mental health conditions | 67 (21%) |
| Hypertension | 59 (18%) |
| Respiratory conditions | 52 (16%) |
| Cancers | 38 (12%) |
| Quality score | Mean |
| Cross-sectional studies (n = 32) | 7.8 out of 10 |
| Cohort studies (n = 26) | 7.9 out of 9 |
| Case-control studies (n = 1) | 7.0 out of 9 |
*Studies can belong to more than one category, meaning individual percentages at times do not sum to 100%