Table 1

Demographic characteristics and risk behaviour for students in high and low response rate schools

	Schools by response rate
Characteristic	High response (%) (unweighted) Ni=1397 Ns=9	Low response (%) (unweighted) Ni=457 Ns=4	Significance (two tailed)	High response (%) (weighted) Ni=1397 Ns=9	All schools (%) (weighted) Ni=1854 Ns=13
Ni, number of individuals; Ns, number of schools; High response, students surveyed in stage 1 or 2 in schools achieving a 70% response rate after stage 1 or 2; Low response, students surveyed in stage 1 or 2 in schools not achieving a 70% response rate after stage 2.
Gender
Female	49	63	0.000	49	53
Male	51	37		51	47
Age
16 or younger	88	86	0.240	87	88
17 or older	12	14		13	13
Ethnicity
African-American	28	35	0.000	28	30
Caribbean-American	27	16		26	23
Asian	8	0.2		8	6
Hispanic/Latino	24	42		26	30
White (including other)	10	5		11	9
Household composition
Both parents	36	18	0.000	35	30
Other relative	8	12		8	10
Single parent	55	70		56	60
Non-legitimate absences
0	74	63	0.000	71	69
1–3	19	26		21	22
4 or more	7	12		9	10
Number of classes cut/skipped
0	42	30	0.000	40	37
1–5	45	52		46	48
6 or more	13	19		14	16
Grades
As or Bs	39	29	0.001	37	34
Cs	37	44		37	39
Ds or Fs	24	27		27	27
Cigarette use in past 4 weeks
% yes	14	19	0.020	15	16
Marijuana use in past 4 weeks
% yes	15	21	0.002	16	17
Alcohol use in past 4 weeks
% yes	36	35	0.820	36	36
Sexually active
% yes	50	53	0.288	51	52
Involved in HIV high risk behaviour
Sometimes—often	13	17	0.025	13	14
Carried weapons to school
1 or more days	12	14	0.365	13	13