Table 1

Characteristics of PHCUs and recruitment process

	Primary care units		Non-responders		Responders		Invited participants
	N	Per cent	N	Per cent	N	Per cent	N	Per cent
Unit size
<2500	7	15.9	139	3.9	2741	13.0	2880	11.7
2500–9999	25	56.8	2766	78.1	12 789	61.0	15 555	63.5
10 000+	12	27.2	636	17.9	5409	25.8	6045	24.6
Unit ownership
Public	8	18.1	491	13.8	4341	20.7	4832	19.7
Private	36	81.8	3050	86.1	16 598	79.2	19 648	80.2
Experience in running public health programmes in the past
No	2	4.5	272	7.68	1449	6.9	1721	7.0
Yes	42	95.4	3269	92.3	19 490	93.0	22 759	92.9
Local promotion
No	34	77.2	2571	72.6	15 774	75.3	18 345	74.9
Yes	10	22.7	970	27.3	5165	24.6	6135	25.0
Mode of invitation
Passive-active	10	22.7	1342	37.9	4886	23.3	6228	25.4
Active-very active	34	77.2	2199	62.1	16 053	76.6	18 252	74.5
Number of personnel involved in the project
1–5	22	50.0	1804	50.9	10 728	51.2	12 532	51.1
>5	22	50.0	1737	49.0	10 211	48.7	11 948	48.8
Working hours devoted to the programme (hours/week)
<10	34	77.2	2775	78.3	15 235	72.7	18 010	73.5
10 or more	10	22.7	766	21.6	5704	27.2	6470	26.4
Working hours per patient (hour)
<0.5	19	44.1	1922	54.5	9953	49.4	11 875	50.1
0.5 to <1	16	37.2	1324	37.5	7666	38.0	899	37.9
1 or more	8	18.6	278	7.8	2523	12.5	2801	11.8
Total	44	100	3541	100	20 939	100	24 480	100

PHCU, primary healthcare unit.