Table 3 Descriptive characteristics of included studies

1.

Abdella and Wabe [28].

2012

Ethiopia

Retrospective

1 year

n.s

Public

1

Urban

Health Officers

384

2.

Adisa et al. [29].

2015

Nigeria

Prospective

3 months

≥15

Public

8

Urban

n.s

400

3.

Afriyie and Tetteh [30].

2013

Ghana

Retrospective

7 months

n/s

Public

1

Urban

Medical assistants, Doctors

120

4.

Afriyie et al. [31].

2015

Ghana

Prospective

6 months

n/s

Public

1

Urban

Medical assistants, doctors

3127

5.

Ahiabu et al. [32].

2015

Ghana

Retrospective

1 year

n/s

Private & Public

4 (public = 1, private = 3)

Urban

Doctors, medical assistants

1600

6.

Angamo et al. [33].

2011

Ethiopia

Prospective

6 weeks

n/s

Public

4

Urban

n.s

3058

7.

Babalola et al. [8].

2011

Nigeria

Retrospective

1 year

19.4 years

Public

20

n/s

Community health workers, physicians, health assistants, pharmacy technicians, nurses and Pharmacist

560

8.

Ball et al. [34]

2000

Zimbabwe

Prospective

n/s

n/s

Public

1

Urban

Nurses

31

9.

Bantie [35]

2014

Ethiopia

Prospective

n/s

n/s

Public

6

n/s

n.s

600

10.

Bexell et al. [36]

1996

Zambia

Retrospective

3 months

n/s

Public

8

Urban

Clinical officers

1167

11.

Boonstra et al. [37]

2002

Botswana

Prospective

n/s

25.5

Public

30

Rural & Urban

Registered nurse, Family nurse practitioner

2994

12.

Boonstra et al. [38]

2005

Botswana

Prospective

n.s

<5

Public

30

Rural & Urban

Nurses

255

13.

Bosu and Ofori-Adjei [39]

2000

Ghana

Retrospective

1 year

15 years

Public

6

Rural

Doctors and medical assistants

585

14.

Desta et al. [40]

1997

Ethiopia

Prospective & Retrospective

Prospective 1–2 days

Retrospective-1 year

n/s

Public

18

n/s

n.s

2340

15.

Dippenar et al. [41]

2006

South Africa

Prospective

2 month

n/s

Public

1

Urban

Doctors, nurses

1000

16.

Enato et al. [42]

2012

Nigeria

Retrospective

6 months

n/s

Public

1

Rural

Doctors, nurses

315

17.

Enato et al. [43]

2013

Nigeria

Retrospective

1 year

n/s

Public

3

Urban

Community health officers

1440

18.

Isah. [44]

2008

Nigeria

Retrospective

1 year

n/s

Private

20

Rural

n.s

2510

19.

Kapp et al. [45]

2013

South Africa

Retrospective

3 months

41.0 years

Public

4

Urban

n.s

400

20.

Katende-Kyenda et al. [46]

2007

South Africa

Retrospective

1 year

n.s

private

9

Urban

n.s

83,655

21.

Krause et al. [47]

1999

Burkina Faso

Prospective

2 months

n/s

Public

9

Rural

nurses

313

22.

Massele and Nsimba. [48]

1997

Tanzania

Prospective

20 days

n/s

Public & Private

40 (public = 20, private = 20)

Urban

n.s

1200

23.

Massele et al. [49]

2001

Tanzania

Retrospective

14 months

n/s

Private

20

Rural & Urban

Doctors

1200

24.

Massele et al. [50]

2007

Tanzania

Retrospective

1 year

n/s

Public & Private

20 (public = 10, Private = 10)

n/s

n.s

2000

25.

Massele et al. [51]

2012

Tanzania

Prospective

3 months

n/s

Public & Private

20 (public = 10, private = 10)

Urban

Clinical officers, and other paramedics

2000

26.

Meyer et al. [52]

2001

South Africa

Retrospective

1 month

n/s

Public

22

n/s

Nurses

1287

27.

Mohlala et al. [53]

2010

South Africa

Prospective

5 months

n/s

Private

36

Rural & Urban

Doctors

276

28.

Nsimba et al. [54]

2004

Tanzania

Retrospective

1 year

n/s

Private

10

n/s

n.s

600

29.

Nsimba [55]

2006

Tanzania

Prospective

n/s

<5 years

Public

10

n/s

n.s

652

30.

Odusanya and Oyediran [7]

2000

Nigeria

Retrospective

6 months

n/s

Public

12

n/s

Community health officers, Public health nurses

650

31.

Olayemi et al. [56]

2006

Nigeria

Prospective & Retrospective

Prospective-2–3days

Retrospective-n/s

n/s

Public

20

Rural & Urban

n.s

1560

32.

Oyeyemi and Ogunleye [57]

2013

Nigeria

Retrospective

1 year

34 years

Public

4

Urban

Medical officer, community health officer, nurses and community health extension workers

600

33.

Phillips-Howard et al. [58]

2003

Kenya

Retrospective

1 year

<5

Public

8

Rural

n.s

9318

34.

Risk et al. [59]

2013

Gambia

Retrospective

1 year

1.71

Public

20

Rural & Urban

n.s

2400

35.

Savadogo et al. [60]

2014

Burkina Faso

Prospective

1 month

<5

Public

2

Urban

n.s

376

36.

Shiferaw et al. [61]

2010

Ethiopia

Retrospective

1 year

n/s

Public

19

n/s

n.s

731

37.

Sisay and Mekonnen [62]

2012

Ethiopia

Retrospective

2 years

n.s

Public

2

Urban

n.s

424

38.

Suleman et al. [63]

2013

Nigeria

Retrospective

3 months

n/s

Public

10

n/s

n.s

222

39.

Tamuno [64]

2011

Nigeria

Retrospective

1 year

n.s

Private

10

Urban

n.s

998

40.

Trap et al. [22]

2002

Zimbabwe

Retrospective

<6 months

n/s

Private

57

Urban

Doctors

1699

41.

Truter et al. [65]

2010

South Africa

Retrospective

8 weeks

n/s

Public

1^m

Rural

Supervised student trainees

4026

42.

Tsega et al. [66]

2012

Ethiopia

Retrospective

1 year

25 years

Public & Private

11 (public = 3, private = 8)

Rural & Urban

n.s

600

43.

Uzochukwu et al. [67]

2002

Nigeria

Retrospective

n/s

n/s

Public

33

n/s

n.s

1650