Table 1 Synthesis of the characteristics of the included studies by level of intervention and PROGRESS factors
Level of intervention | Patient level | Provider level | Health care systems level | Total QI strategies | ||||
|---|---|---|---|---|---|---|---|---|
Total of studies | 29 | 3 | 26 | 58 | ||||
| Â | N | % | N | % | N | % | N | % |
Sample characteristics | ||||||||
 Age | 55.13 |  - | 55.37 |  - | 53.82 |  - | 55.06 |  - |
 Sex, female (%) |  | 64.05 |  | 58.69 |  | 57.84 |  | 60.20 |
Baseline HgA1c (%; mmol/mol) | 8.88; 74 | 7.0–11.8; 53–105 | 9.53; 81 | 8.1–12.05; 31–109 | 8.51; 70 | 7.6–10.5; 60–91 | 8.88; 74 | 7.0–12.05; 53–109 |
Progress factors reported at baseline | ||||||||
 Place of residence | 29 |  50 | 3 |  5.2 | 26 |  44.8 | 58 |  - |
 Race/ethnicity | 26 |  49.1 | 3 |  5.7 | 24 |  45.3 | 53 |  - |
 Occupation | 12 |  54.5 | – |  - | 10 |  45.5 | 22 |  - |
 Gender/sex | 24 |  46.2 | 3 |  5.8 | 25 |  48.1 | 52 |  - |
 Religion | – |  - | – |  - | – |  - | – |  - |
 Education | 26 |  57.7 | 1 |  2.2 | 18 |  40.1 | 45 |  - |
 Socioeconomic status (SES) | – |  - | – |  - | – |  - | – |  - |
 Income | 20 |  62.5 | – |  - | 12 |  37.5 | 32 |  - |
 Social capital | 10 |  62.5 |  - |  - | 6 |  37.5 | 16 |  - |
 Age | 28 |  50.0 | 3 |  5.4 | 25 |  44.7 | 56 |  - |
 Disability | – |  - | – |  - | – |  - | – |  - |
 Sexual orientation | – |  - | – |  - | – |  - | – |  - |
Study characteristics | ||||||||
Year of publication | ||||||||
  2005–2010 | 11 | 19 | 2 | 3.5 | 11 | 19 | 24 | 41.4 |
  2011–2016 | 18 | 31 | 1 | 1.7 | 15 | 25.9 | 34 | 58.6 |
 Study location | ||||||||
  North America | 25 | 86.2 | 3 | 100 | 22 | 85 | 47 |  |
  UK | 1 | 3.4 | – |  - | 1 | 3.8 | 2 | 3.4 |
  Australia | – | – | – |  - | 2 |  - | 2 | 3.4 |
  Asia | 3 | 10.4 | – |  - | 1 | 7.7 | 4 | 6.9 |
Duration of study (months) | 10 | 3–26 | 4.5 | 0.25–36 | 12 | 6–60 | 8.9 | 0.25–60 |
Average sample size (range) | 190 (56–526) | 1573 (182–4138) | 290 (65–1665) | 684 (50–4138) | ||||