Supplementary Tables
Table S1. Contributions to trends in Ever used a Condom (among sexually experienced)
---------------------------------------------------------------------------------------------|
year
comparison |1993 1996 1997 1999 2000 2001 2002 2003 2005 2006 2007
-----------------------------+---------------------------------------------------------------Changed answer Ever to never|
0
-32
-84
-96 -150 -165 -194 -153 -179 -128 -194
Changed answer Never to ever|
0
107
143
118
186
208
185
198
173
263
179
In migrant-ever|
0
89
71
131
113
95
87
116
127
97
85
Out migrant-was ever|
0
-52
-66 -103
-66
-74
-96
-88 -222
-81 -107
Newly interviewed-ever|
0
151
136
193
110
212
169
175
156
206
246
Not interviewed-was ever|
0
-42 -103
-91 -190 -150 -211 -213 -238 -173 -241
New ans question-ever|
0
66
1
2
0
0
0
0
0
2
0
Didn't ans question-was ever|
0
-1
-17
0
-2
0
-1
0
-2
0
-2
Age 13-ever|
0
1
0
3
2
1
2
1
1
0
1
Died-was ever|
0
-1
-1
-8
-11
-13
-15
-16
-11
-9
-8
Newly experienced-ever|
0
0
0
79
51
62
65
54
62
39
46
Was experienced-was ever|
0
0
0
-4
-9
-18
-17
-13
-6
-9
-13
---------------------------------------------------------------------------------------------net new ‘ever’ responses|
0
286
80
224
34
158
-26
61 -139
207
-8
---------------------------------------------------------------------------------------------Changed answer Ever to never|
0
32
84
96
150
165
194
153
179
128
194
Changed answer Never to ever|
0 -107 -143 -118 -186 -208 -185 -198 -173 -263 -179
In migrant-never |
0
322
180
330
247
187
162
139
192
108
90
Out migrant-was never |
0 -420 -181 -225 -159 -105 -149 -126 -297 -107
-82
Newly interviewed-never |
0
749
480
664
364
499
406
319
362
309
338
Not interviewed-was never |
0 -612 -542 -275 -508 -400 -445 -465 -400 -347 -394
New ans question-never |
0
323
7
9
0
9
6
1
0
2
3
Didn't ans question-was never|
0
-5 -449
-1
-7
-7
0
0
-1
-1
-6
Age 13-never |
0
172
3
6
7
5
5
5
5
1
3
Died-was never |
0
-42
-35
-42
-41
-46
-49
-56
-43
-30
-29
Newly experienced-never |
0
0
0
141
86
70
66
63
93
39
46
Was experienced-was never |
0
0
0
-11
-43
-47
-43
-31
-15
-33
-12
---------------------------------------------------------------------------------------------net new never responses |
0
412 -596
574
-90
122
-32 -196
-98 -194
-28
-------------------------------------------------------------------------------------------------------------------------+----------------------------------------------------------------Ever used condom | 164
450
530
754
788
946
920
981
842 1,049 1,041
Never used condom |2,010 2,422 1,826 2,400 2,310 2,432 2,400 2,204 2,106 1,912 1,884
---------------------------------------------------------------------------------------------Percent used condom | 7.54 15.67 22.50 23.91 25.44 28.00 27.71 30.80 28.56 35.43 35.59
---------------------------------------------------------------------------------------------1
New ans question = Interviewed the previous time that the question was asked, but did not answer the specific question
2
Didn’t ans question = Interviewed but did not answer the specific question – did answer the previous time the question was asked
3
Newly experienced: respondent reported having ever had sex, but had never had sex the previous round
4
Was experienced: respondent reported never having had sex, but reported having had sex in the previous round (inconsistent sequence)
5
Whether or not the respondent had ever had sex was not asked in 1995 and 1996. Therefore, we are unable to determine whether the
individual was newly sexually experienced in 1996 and 1997.
Table S2. Contributions to trends in 2+ sexual partners in past year (among sexually experienced)
------------------------------------------------------------------------------------------|
year
comparison | 1996 1997 1999 2000 2001 2002 2003 2004 2005 2006 2007
-------------------------+----------------------------------------------------------------Changed answer 2+ to <=1 |
0
-99
-91 -132 -112 -123 -131
-93 -100
-65 -108
Changed answer <=1 to 2+ |
0
59
100
112
117
115
78
114
77
99
55
In migrant 2+ |
0
44
55
47
28
36
35
27
20
22
12
Out migrant-was 2+ |
0
-33
-47
-33
-16
-27
-26
-37
-33
-23
-32
Newly interviewed 2+ |
0
75
137
65
109
78
67
83
59
66
53
Not interviewed-was 2+ |
0
-76
-40 -119
-98 -116 -100
-85
-99
-66
-88
New ans question 2+ |
0
3
0
0
0
0
0
0
0
0
0
Age 13 2+ |
0
0
1
1
2
1
0
0
0
0
0
Died-was 2+ |
0
-1
-4
-7
-6
-5
-8
-5
0
0
-5
Newly experienced 2+ |
0
23
61
27
25
27
16
18
17
13
12
Was experienced 2+ |
0
-16
-2
-14
-14
-13
-8
-3
-6
-6
-4
------------------------------------------------------------------------------------------net new 2+ responses |
0
-21
170
-53
35
-27
-77
19
-65
40 -105
------------------------------------------------------------------------------------------Changed answer 2+ to <=1 |
0
99
91
132
112
123
131
93
100
65
108
Changed answer <=1 to 2+ |
0
-59 -100 -112 -117 -115
-78 -114
-77
-99
-55
In migrant <=1 |
0
207
406
314
254
213
220
220
170
183
163
Out migrant-was <=1 |
0 -106 -277 -192 -163 -218 -188 -236 -224 -165 -157
Newly interviewed <=1 |
0
527
720
411
604
497
427
522
335
448
529
Not interviewed-was <=1 |
0 -280 -320 -579 -455 -543 -578 -412 -624 -454 -546
Age 13 <=1 |
0
3
8
8
4
6
6
2
5
1
4
Died=was <=1 |
0
-17
-45
-45
-52
-60
-64
-48
-54
-39
-32
Newly experienced <=1 |
0
312
189
110
108
105
103
100
114
66
83
Was experienced <=1 |
0
-34
-13
-38
-52
-50
-36
-35
-24
-39
-24
------------------------------------------------------------------------------------------net new <=1 responses |
0
652
659
9
243
-42
-57
92 -279
-33
73
-------------------------------------------------------------------------------------------------------------------+----------------------------------------------------------------0-1 sex partners |1,387 2,039 2,698 2,707 2,950 2,908 2,851 2,943 2,664 2,631 2,704
2+ sex partners | 307
286
456
403
438
411
334
353
288
328
223
------------------------------------------------------------------------------------------Percent 2+ partners |18.12 12.30 14.46 12.96 12.93 12.38 10.49 10.71 9.76 11.08 7.62
------------------------------------------------------------------------------------------1
New ans question = Interviewed the previous time that the question was asked, but did not answer the specific question
2
Didn’t ans question = Interviewed but did not answer the specific question – did answer the previous time the question was asked
Table S3. Contributions to trends in age at first sex among 17-20 year olds
--------------------------------------------------------------------------------------------------|
year
comparison | 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
---------------------------------+----------------------------------------------------------------SAME RESPONDENTS
|
Same response |
0
86
97
89
107
132
145
135
125
112
113
Increase 1 yr |
0
25
29
42
36
28
21
29
21
16
12
Decrease 1 yr |
0
20
17
14
25
23
18
23
20
16
14
Increase 2+ yrs |
0
15
23
34
30
35
33
35
11
16
8
Decrease 2+ yrs |
0
18
21
18
19
5
12
12
17
7
17
Censored to New sexual debut |
0
41
61
47
43
44
40
46
35
25
26
Ever sex to Never sex (censored) |
0
11
16
19
18
22
10
10
8
11
14
--------------------------------------------------------------------------------------------------Sum of Same Respondents |
0
216
264
263
278
289
279
290
237
203
204
--------------------------------------------------------------------------------------------------NEW RESPONDENTS
|
New answer (was DK) |
0
0
14
3
11
2
0
7
3
1
1
In Migrant |
0
78
77
95
65
66
72
56
46
61
46
Newly interviewed |
0
125
105
94
164
111
117
128
79
99
110
Newly answered question |
0
0
2
1
1
0
0
0
0
0
2
Age 17 |
0
97
134
104
139
136
145
143
124
114
115
--------------------------------------------------------------------------------------------------Sum of New Respondents |
0
300
332
297
380
315
334
334
252
275
274
--------------------------------------------------------------------------------------------------LOST RESPONDENTS
|
Not answered (DK) |
0
-14
-9
-18
-6
-5
-12
-7
-7
-1
-4
Out Migrant |
0
-82
-71
-84
-72 -110
-92 -120 -117
-85
-82
Not interviewed |
0
-85
-84 -168 -127 -179 -147 -132 -185 -141 -131
Didn't answer question |
0
-14
-10
-5
-4
-4
-2
-2
-5
-2
-3
Died |
0
-1
-2
-3
-2
-2
-1
-4
-2
-1
-5
Age 21 |
0
-69
-76
-55
-71
-69
-71
-58
-71
-56
-49
--------------------------------------------------------------------------------------------------Sum of Lost Respondents |
0 -265 -252 -333 -282 -369 -325 -323 -387 -286 -274
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------MEDIAN AGE AT FIRST SEX
Male | 18.5 18.0 17.6 17.8 18.4 18.8 18.5 18.9 19.8 20.6 20.5
Female | 16.8 17.4 17.2 17.4 17.4 17.7 17.8 17.9 17.9 18.2 18.6
--------------------------------------------------------------------------------------------------SAMPLE SIZE
Male | 246
253
290
257
318
285
302
309
241
229
237
Female | 235
263
306
303
340
319
311
315
248
249
241
--------------------------------------------------------------------------------------------------Total Respondents | 481
516
596
560
658
604
613
624
489
478
478
---------------------------------------------------------------------------------------------------
DK = response was “don’t know”, which for purposes of analysis was set to missing.
1
Table S4. Contributions to mean casual partners in past year (among sexually experienced)
-----------------------------------------------------------------------------------|
year
comparison| 1997 1999 2000 2001 2003 2004 2005 2006 2007
------------------------------+----------------------------------------------------Changed answer to Lower number|
0
-88 -136 -119 -150 -119 -129 -110 -108
Change answer to Higher number|
0
95
122
157
91
152
98
93
58
In migrant-high|
0
43
43
28
36
31
21
18
10
Out migrant-was high|
0
-52
-21
-27
-72
-42
-53
-29
-26
Newly interviewed-high|
0
75
36
89
49
69
47
46
33
Not interviewed-was high|
0
-28
-71
-57
-89
-65
-88
-64
-49
New ans question-high|
0
0
0
2
0
0
0
0
0
Didn't ans question-was high|
0
-1
0
-1
0
0
0
0
0
Age 13-high|
0
3
6
3
1
0
0
0
1
Died-was high|
0
-2
-6
-4
-3
-1
-1
0
-2
Newly experienced-high|
0
38
44
49
54
42
41
26
31
Was experienced-was high|
0
-6
-14
-17
-14
-12
-11
-11
-6
-----------------------------------------------------------------------------------net new higher responses|
0
77
3
103
-97
55
-75
-31
-58
-----------------------------------------------------------------------------------Changed answer to Lower number|
0
88
136
119
150
119
129
110
108
Change answer to Higher number|
0
-95 -122 -157
-91 -152
-98
-93
-58
In migrant-low|
0
418
317
254
361
215
169
186
165
Out migrant-was low|
0 -271 -204 -152 -430 -231 -204 -159 -163
Newly interviewed-low|
0
782
439
621
464
536
347
467
547
Not interviewed-was low|
0 -332 -627 -493 -607 -432 -634 -456 -584
New ans question-low|
0
0
2
5
1
1
0
1
5
Didn't ans question-was low|
0
-1
-8
0
-1
0
-1
-4
-1
Age 13-low|
0
6
3
3
5
2
5
1
3
Died-was low|
0
-47
-46
-53
-55
-52
-53
-39
-35
Newly experienced-low|
0
212
92
84
118
76
90
53
64
Was experienced-was low|
0
-9
-38
-49
-18
-26
-19
-34
-22
-----------------------------------------------------------------------------------net new lower responses|
0
751
-56
182 -103
56 -269
33
29
-----------------------------------------------------------------------------------Mean casual partners/year|0.170 0.214 0.202 0.236 0.156 0.160 0.153 0.136 0.088
Sample Size|2,324 3,152 3,099 3,384 3,184 3,295 2,951 2,953 2,924
-----------------------------------------------------------------------------------1
High: Respondent reported a higher number than the mean (since the mean was < 1 in all years, this implies that the respondent reported 1
or more casual partners)
2
Low: Respondent reported a lower number than the mean
3
Newly experienced: respondent reported having ever had sex, but had never had sex the previous round
4
Was experienced: respondent reported never having had sex, but reported having had sex in the previous round (inconsistent sequence)
Table S5. Contributions to trends in ever had sex among 15-19 year olds
------------------------------------------------------------------------------------------------------|
year
comparison|1993 1994 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
---------------------------+--------------------------------------------------------------------------Change Answer Ever to never|
0 -15
-3
-14
-31
-31
-36
-36
-30
-22
-12
-20
-12
Change Ans never to ever|
0
27
38
93
105
78
71
80
79
70
79
51
57
In migrant-ever|
0
26
87
63
60
76
51
52
59
42
35
38
29
Out migrant-was ever|
0 -30
-20
-45
-32
-44
-49
-46
-43
-60
-54
-41
-28
Newly interviewed-ever|
0
48
60
75
63
59
83
59
63
47
32
44
43
Not interviewed-was ever|
0 -59
-4
-32
-54
-77
-47
-57
-50
-54
-52
-42
-42
New ans question-ever|
0
2
0
1
0
0
0
0
0
0
0
0
1
Age 15-ever|
0
8
67
33
43
31
37
34
19
21
27
17
18
Age 20-was ever|
0 -56 -144
-90
-95 -111 -106 -132
-91 -100
-95
-78
-78
Died-was ever|
0
-2
0
-1
-1
0
-1
-2
0
0
-1
0
-2
------------------------------------------------------------------------------------------------------net new ever responses|
0 -51
81
83
58
-19
3
-48
6
-56
-41
-31
-14
------------------------------------------------------------------------------------------------------Change Answer Ever to never|
0
15
3
14
31
31
36
36
30
22
12
20
12
Change Ans never to ever|
0 -27
-38
-93 -105
-78
-71
-80
-79
-70
-79
-51
-57
In migrant-never|
0
13
35
19
21
25
21
16
21
24
16
24
18
Out migrant-was never|
0 -38
-90
-41
-52
-48
-52 -108
-74
-71
-97
-74
-68
Newly interviewed-never|
0
54
113
75
47
59
132
69
68
89
60
53
86
Not interviewed-was never|
0 -106
-45
-73
-80 -127 -125 -161 -157 -127 -168 -159 -165
New ans ques-never|
0
2
0
0
1
0
0
0
0
0
0
0
0
Didn't ans ques-was never|
0
-1
-1
0
0
0
0
0
0
0
0
-1
0
Age 15-never|
0
99
248
166
210
212
228
220
225
221
234
241
222
Age 20-was never|
0 -21 -111
-34
-34
-36
-27
-42
-42
-46
-41
-38
-36
Died-was never|
0
-1
-1
0
-1
0
-1
-1
-1
-3
-2
0
0
------------------------------------------------------------------------------------------------------net new never responses|
0 -11
113
33
38
38
141
-51
-9
39
-65
15
12
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Ever had sex| 238 187
268
351
409
390
393
345
351
295
254
223
209
Never had sex| 335 324
437
470
508
546
687
636
627
666
601
616
628
------------------------------------------------------------------------------------------------------Percent ever had sex|41.5 39.6 44.0 46.7 48.3 45.4 40.1 39.6 39.6 35.2 33.0 29.2 27.8
------------------------------------------------------------------------------------------------------1
In migrants in 2000 (round 11) include those who joined the cohort in the 10 new villages
New ans question = Interviewed the previous time that the question was asked, but did not answer the specific question
3
Didn’t ans question = Interviewed but did not answer the specific question – did answer the previous time the question was asked
2