Background
Non-response
Recruitment effort
Attrition
Sample and survey characteristics related to success of extra recruitment effort
Methods
Participants
Measures
Sociodemographic characteristics
Educational level
Sociometric status
Substance use
Psychopathology
Data analysis
Results
T1 | T2 | T3 | T4 | |
---|---|---|---|---|
n
| 2,230 | 2,149 | 1,816c
| 1,881d
|
mean age (SD) | 11.09 (0.56) | 13.56 (0.53) | 16.27 (0.73) | 19.1 (0.60) |
% girls | 50.8 | 51 | 52.3 | 52.3 |
response rate (%) | 76a
| 96.4b
| 81.4b
| 84.3b
|
Effects of extensive recruitment efforts eight years later
T1 | T2 | T3 | T4 | ||||
---|---|---|---|---|---|---|---|
n | n | % | n | % | n | % | |
T1-easy-to-recruit | 2,085 | 2,015 | 96.6 | 1,730 | 83.0 | 1,792 | 85.9 |
T1-hard-to-recruit | 145 | 134 | 92.4 | 86 | 59.3 | 89 | 61.4 |
OR | 95% CI | OR | 95% CI | OR | 95% CI | ||
T1-hard-to-recruita
| 0.42* | 0.22 – 0.82 | 0.30* | 0.21 – 0.43 | 0.26* | 0.18 – 0.37 |
T1-easy-to-recruit-retainer | T1-hard-to-recruit-retainer (ref.) | T1-easy-to-recruit-dropout | T1-hard-to-recruit-dropout | |||||||
---|---|---|---|---|---|---|---|---|---|---|
( n = 1,549) | ( n = 55) | ( n = 222) | ( n = 33) | |||||||
n(%) | OR | 95% CI | n(%) | n(%) | OR | 95% CI | n(%) | OR | 95% CI | |
T1 Sociodemo-graphics
| ||||||||||
Non-western immigrant | 102 (6.6) | 0.40* | 0.19-0.86 | 10 (18.2) | 40 (18.0) | 1.03 | 0.47-2.29 | 14 (42.4) | 2.72 | 0.98-7.58 |
(univariate effects)
|
0.32*
|
0.16-0.65
|
0.99
|
0.46-2.13
|
3.32*
|
1.25-8.77
| ||||
Lower education mother (≤lower tracks of sec. educ.) | 491 (31.7) | 0.44* | 0.24-0.79 | 33 (60.0) | 132 (59.5) | 1.06 | 0.56-2.00 | 22 (66.7) | 1.25 | 0.48-3.24 |
(univariate effects)
|
0.31*
|
0.18-0.54
|
0.98
|
0.54-1.79
|
1.33
|
0.54-3.29
| ||||
Low family income (<€1,135) | 183 (11.8) | 0.48* | 0.25-0.91 | 17 (30.9) | 60 (27.0) | 0.83 | 0.42-1.65 | 15 (45.5) | 1.35 | 0.51-3.57 |
(univariate effects)
|
0.30*
|
0.17-0.54
|
0.83
|
0.44-1.58
|
1.86
|
0.76-4.55
| ||||
Low IQ (wisc < 85) | 213 (13.8) | 0.55 | 0.30-1.03 | 18 (32.7) | 65 (29.3) | 0.88 | 0.45-1.73 | 13 (39.4) | 1.08 | 0.41-2.81 |
(univariate effects)
|
0.33*
|
0.18-0.59
|
0.85
|
0.45-1.60
|
1.34
|
0.55-3.28
| ||||
mean (SD) | OR | 95% CI | mean (SD) | mean (SD) | OR | 95% CI | mean (SD) | OR | 95% CI | |
T1 Psychopathology
| ||||||||||
CBCL Internalizing problems | 0.25 (0.19) | 1.33 | 0.96-1.84 | 0.24 (0.17) | 0.25 (0.20) | 1.07 | 0.76-1.52 | 0.30 (0.24) | 1.34 | 0.84-2.16 |
(univariate effects)
|
1.00
|
0.76-1.31
|
1.03
|
0.76-1.38
|
1.26
|
0.85-1.86
| ||||
CBCL Externalizing problems | 0.23 (0.19) | 0.70* | 0.53-0.91 | 0.31 (0.27) | 0.30 (0.26) | 0.95 | 0.71-1.27 | 0.28 (0.23) | 0.74 | 0.47-1.17 |
(univariate effects)
|
0.71*
|
0.56-0.89
|
0.97
|
0.76-1.23
|
0.89
|
0.61-1.30
|
Effects of extensive recruitment efforts at age 19
Sociodemographic characteristics
T4-easy-to-recruit (ref.) | T4-hard-to-recruit | Non-responder T4 | Drop-out since T2 or T3 | |||||||
---|---|---|---|---|---|---|---|---|---|---|
n(%) | n(%) | OR | 95% CI | n(%) | OR | 95% CI | n(%) | OR | 95% CI | |
T1 Socio-demographics
| ||||||||||
Girl | 894 (55.5) | 89 (32.8) | 0.39* | 0.30-0.51 | 49 (36.6) | 0.46* | 0.32-0.67 | 100 (46.5) | 0.70* | 0.52-0.93 |
Non-western immigrant | 122 (7.6) | 36 (13.3) | 1.87* | 1.26-2.78 | 29 (21.6) | 3.37* | 2.15-5.29 | 50 (23.3) | 3.70* | 2.56-5.33 |
Parents divorced | 304 (18.9) | 72 (26.6) | 1.55* | 1.16-2.09 | 49 (36.6) | 2.48* | 1.71-3.60 | 51 (23.7) | 1.34 | 0.95-1.87 |
Single parent | 30 (1.9) | 6 (2.2) | 1.19 | 0.49-2.89 | 6 (4.5) | 2.47* | 1.01-6.04 | 11 (5.1) | 2.84* | 1.40-5.75 |
No siblings | 125 (7.9) | 30 (11.2) | 1.47 | 0.97-2.25 | 16 (12.1) | 1.61 | 0.93-2.81 | 30 (14.9) | 2.05* | 1.34-3.15 |
Lower education mother (≤lower tracks of sec. educ.) | 503 (32.0) | 113 (43.0) | 1.60* | 1.23-2.09 | 82 (64.1) | 3.78* | 2.60-5.51 | 119 (60.4) | 3.24* | 2.39-4.39 |
Lower education father (≤lower tracks of sec. educ.) | 395 (28.3) | 84 (38.9) | 1.61* | 1.20-2.17 | 52 (50.5) | 2.58* | 1.72-3.86 | 78 (48.4) | 2.38* | 1.71-3.31 |
Low family income (<€1,135) | 187 (12.8) | 50 (20.2) | 1.72* | 1.22-2.43 | 43 (37.1) | 4.02* | 2.67-6.03 | 58 (31.9) | 3.19* | 2.25-4.51 |
T1 Low SEP (lowest 25%) | 315 (19.8) | 83 (31.0) | 1.81* | 1.36-2.41 | 73 (55.3) | 5.00* | 3.47-7.19 | 82 (40.8) | 2.78* | 2.05-3.78 |
Low IQ (wisc < 85) | 221 (13.8) | 61 (22.6) | 1.83* | 1.33-2.52 | 51 (38.6) | 3.95* | 2.70-5.76 | 55 (25.8) | 2.18* | 1.56-3.06 |
T4 Socio-demographics
| ||||||||||
Lower education mother (≤lower tracks of sec. educ.) | 412 (29.3) | 86 (40.6) | 1.65* | 1.22-2.21 | - | - | ||||
Lower education father (≤lower tracks of sec. educ.) | 316 (25.3) | 71 (39.9) | 1.96* | 1.41-2.71 | - | - | ||||
Low family income (<€1,150) | 71 (5.6) | 20 (11.0) | 2.08* | 1.23-3.50 | - | - | ||||
T4 Low SEP (lowest 25%) | 341 (23.4) | 78 (35.6) | 1.82* | 1.34-2.46 | - | - | ||||
Mean (SD) | Mean (SD) | OR | 95% CI | Mean (SD) | OR | 95% CI | Mean (SD) | OR | 95% CI | |
Educational level (adjusted for age)
| ||||||||||
T2 Educational level | 4.13 (1.32) | 3.62 (1.28) | 0.64* | 0.56-0.74 | 3.07 (1.17) | 0.42* | 0.34-0.52 | 3.42 (1.27) | 0.57* | 0.48-0.68 |
T3 Educational level | 7.11 (1.57) | 6.46 (1.43) | 0.61* | 0.52-0.73 | 5.77 (1.28) | 0.35* | 0.28-0.44 | - |
Sociometric status
T4-easy-to-recruit (ref.) | T4-hard-to-recruit | Non-responder T4 | Drop-out since T2 or T3 | |||||||
---|---|---|---|---|---|---|---|---|---|---|
Mean ( SD ) | Mean ( SD ) | OR | 95% CI | Mean ( SD ) | OR | 95% CI | Mean ( SD ) | OR | 95% CI | |
T1 Sociometric Characteristics
| ||||||||||
Peer acceptance | 29 (15) | 27 (17) | 0.88 | 0.72-1.08 | 26 (16) | 0.80 | 0.60-1.06 | 27 (16) | 0.87 | 0.71-1.07 |
Peer rejection | 11 (12) | 15 (15) | 1.29* | 1.07-1.56 | 18 (16) | 1.50* | 1.19-1.88 | 16 (16) | 1.35* | 1.13-1.63 |
Bullying | 05 (07) | 07 (09) | 1.35* | 1.13-1.62 | 10 (13) | 1.56* | 1.27-1.93 | 08 (11) | 1.39* | 1.16-1.66 |
Victimization | 04 (07) | 04 (08) | 1.05 | 0.86-1.28 | 05 (08) | 1.16 | 0.93-1.37 | 05 (10) | 1.15 | 0.97-1.37 |
Helping | 22 (14) | 19 (14) | 0.79* | 0.64-0.98 | 18 (12) | 0.75 | 0.55-1.01 | 22 (15) | 0.97 | 0.79-1.18 |
T2 Sociometric Characteristics
| ||||||||||
Peer acceptance | 21 (12) | 22 (14) | 1.13 | 0.93-1.38 | 27 (14) | 1.61* | 1.25-2.06 | 20 (13) | 0.97 | 0.75-1.25 |
Peer rejection | 11 (13) | 13 (18) | 1.15 | 0.95-1.39 | 12 (14) | 1.09 | 0.83-1.45 | 17 (15) | 1.44* | 1.19-1.75 |
Bullying | 02 (04) | 03 (08) | 1.45* | 1.19-1.76 | 05 (11) | 1.64* | 1.32-2.03 | 05 (09) | 1.66* | 1.37-2.02 |
Victimization | 02 (05) | 03 (08) | 1.26* | 1.06-1.50 | 05 (09) | 1.48* | 1.22-1.79 | 03 (06) | 1.21 | 0.97-1.50 |
Helping | 25 (13) | 22 (14) | 0.76* | 0.61-0.94 | 27 (13) | 1.18 | 0.90-1.54 | 20 (10) | 0.68* | 0.52-0.89 |
Substance use
T4-easy-to-recruit (ref.) | T4-hard-to-recruit | Non-responder T4 | Drop-out since T2 or T3 | |||||||
---|---|---|---|---|---|---|---|---|---|---|
n(%) | n(%) | OR | 95% CI | n(%) | OR | 95% CI | n(%) | OR | 95% CI | |
Lifetime substance use
| ||||||||||
T2 Tobacco lifetime prevalence | 533 (33.7) | 107 (44.0) | 1.55* | 1.18-2.03 | 62 (50.8) | 2.03* | 1.40-2.94 | 56 (39.7) | 1.30 | 0.91-1.84 |
T2 Alcohol lifetime prevalence | 1,162 (73.9) | 194 (79.8) | 1.40* | 1.00-1.95 | 92 (76.7) | 1.16 | 0.75-1.80 | 103 (72.5) | 0.93 | 0.64-1.37 |
T2 Cannabis lifetime prevalence | 100 (6.3) | 28 (11.6) | 1.94* | 1.25-3.02 | 11 (9.3) | 1.52 | 0.79-2.92 | 14 (10.1) | 1.65 | 0.92-2.98 |
T3 Tobacco lifetime prevalence | 819 (57.1) | 89 (70.6) | 1.81* | 1.21-2.69 | 69 (70.4) | 1.79* | 1.14-2.79 | - | ||
T3 Alcohol lifetime prevalence | 1,345 (93.9) | 125 (98.4) | 4.04 | 0.98-16.62 | 92 (93.9) | 0.99 | 0.42-2.33 | - | ||
T3 Cannabis lifetime prevalence | 439 (30.7) | 45 (35.4) | 1.24 | 0.85-1.81 | 35 (36.5) | 1.29 | 0.84-1.99 | - | ||
T4 Tobacco lifetime prevalence | 1,153 (72.7) | 100 (81.3) | 1.64* | 1.03-2.61 | - | - | ||||
T4 Alcohol lifetime prevalence | 1,146 (98.2) | 121 (99.2) | 2.27 | 0.31-16.81 | - | - | ||||
T4 Cannabis lifetime prevalence | 841 (53.1) | 66 (55.0) | 1.08 | 0.75-1.57 | - | - |
Psychopathology
T4-easy-to-recruit (ref.) | T4-hard-to-recruit | Non-responder T4 | Drop-out since T2 or T3 | |||||||
---|---|---|---|---|---|---|---|---|---|---|
Mean ( SD ) | Mean ( SDs ) | OR | 95% CI | Mean ( SD ) | OR | 95% CI | Mean ( SD ) | OR | 95% CI | |
Psychopathology
| ||||||||||
T1 CBCL Int. | 0.24 (0.19) | 0.24 (0.21) | 0.97 | 0.85-1.12 | 0.24 (0.19) | 0.97 | 0.80-1.17 | 0.27 (0.21) | 1.11 | 0.96-1.29 |
T1 CBCL Ext | 0.22 (0.19) | 0.29 (0.21) | 1.37* | 1.21-1.56 | 0.31 (0.26) | 1.46* | 1.24-1.71 | 0.29 (0.24) | 1.36* | 1.18-1.57 |
T1 CBCL Total | 0.24 (0.16) | 0.27 (0.18) | 1.22* | 1.07-1.39 | 0.28 (0.20) | 1.27* | 1.07-1.50 | 0.28 (0.19) | 1.30* | 1.13-1.51 |
T2 CBCL Int | 0.20 (0.18) | 0.19 (0.17) | 0.95 | 0.82-1.10 | 0.20 (0.18) | 1.02 | 0.83-1.25 | 0.22 (0.21) | 1.15 | 0.97-1.37 |
T2 CBCL Ext | 0.16 (0.18) | 0.21 (0.21) | 1.30* | 1.14-1.47 | 0.22 (0.27) | 1.35* | 1.13-1.60 | 0.20 (0.20) | 1.23* | 1.03-1.46 |
T2 CBCL Total | 0.18 (0.15) | 0.20 (0.16) | 1.16* | 1.02-1.33 | 0.21 (0.18) | 1.24* | 1.03-1.49 | 0.21 (0.17) | 1.22* | 1.02-1.45 |
T3 CBCL Int | 0.19 (0.19) | 0.21 (0.20) | 1.11 | 0.94-1.32 | 0.17 (0.18) | 0.89 | 0.67-1.19 | - | ||
T3 CBCL Ext | 0.16 (0.18) | 0.27 (0.27) | 1.49* | 1.29-1.72 | 0.20 (0.24) | 1.19 | 0.94-1.50 | - | ||
T3 CBCL Total | 0.17 (0.15) | 0.23 (0.19) | 1.39* | 1.19-1.62 | 0.19 (0.19) | 1.14 | 0.90-1.46 | - | ||
T1 YSR Int | 0.37 (0.24 | 0.33 (0.21) | 0.84* | 0.73-0.96 | 0.34 (0.24) | 0.87 | 0.72-1.05 | 0.36 (0.26) | 0.94 | 0.81-1.09 |
T1 YSR Ext | 0.27 (0.19) | 0.28 (0.20) | 1.07 | 0.94-1.21 | 0.27 (0.22) | 1.03 | 0.86-1.23 | 0.29 (0.21) | 1.10 | 0.95-1.26 |
T1 YSR Total | 0.34 (0.19) | 0.33 (0.18) | 0.92 | 0.80-1.05 | 0.33 (0.19) | 0.95 | 0.79-1.14 | 0.34 (0.21) | 0.99 | 0.86-1.14 |
T2 YSR Int | 0.34 (0.24) | 0.29 (0.24) | 0.82* | 0.71-0.95 | 0.30 (0.25) | 0.83 | 0.68-1.02 | 0.30 (0.26) | 0.85 | 0.71-1.03 |
T2 YSR Ext | 0.28 (0.19) | 0.31 (0.21) | 1.15* | 1.01-1.31 | 0.30 (0.23) | 1.09 | 0.91-1.31 | 0.28 (0.23) | 1.01 | 0.85-1.21 |
T2 YSR Total | 0.33 (0.18) | 0.32 (0.19) | 0.96 | 0.84-1.11 | 0.31 (0.19) | 0.90 | 0.74-1.09 | 0.31 (0.20) | 0.87 | 0.73-1.05 |
T3 YSR Int | 0.32 (0.25) | 0.26 (0.23) | 0.75* | 0.60-0.92 | 0.30 (0.25) | 0.94 | 0.76-1.16 | - | ||
T3 YSR Ext | 0.31 (0.21) | 0.36 (0.22) | 1.25* | 1.06-1.48 | 0.38 (0.25) | 1.36* | 1.13-1.64 | - | ||
T3 YSR Total | 0.33 (0.18) | 0.32 (0.17) | 0.94 | 0.78-1.14 | 0.35 (0.18) | 1.10 | 0.90-1.35 | - | ||
T4 ASR Int | 0.25 (0.25) | 0.26 (0.27) | 1.04 | 0.86-1.26 | - | - | ||||
T4 ASR Ext | 0.23 (0.21) | 0.25 (0.24) | 1.09 | 0.87-1.36 | - | - | ||||
T4 ASR Total | 0.28 (0.21) | 0.31 (0.25) | 1.15 | 0.92-1.43 | - | - | ||||
n(%) | n(%) | OR | 95% CI | |||||||
CIDI T4: Int. diagnosis | 646 (42.9) | 37 (48.1) | 1.30 | 0.78-1.95 | - | - | ||||
CIDI T4: Ext. diagnosis | 540 (35.8) | 39 (50.6) | 1.84* | 1.16-2.91 | - | - | ||||
CIDI T4: Total problem diagnosis | 917 (60.8) | 53 (68.8) | 1.42 | 0.87-2.33 | - | - |
T4-easy-to-recruit (n = 1,359) (ref.) | T4-hard-to-recruit (n = 213) | T4-non-responder (n = 98) | Drop-out since T2 or T3 (n = 150) | |||||||
---|---|---|---|---|---|---|---|---|---|---|
n(%) | n(%) | OR | 95% CI | n(%) | OR | 95% CI | n(%) | OR | 95% CI | |
T1 Recruitment Effort
| ||||||||||
Hard to recruit | 42 (3.1) | 8 (3.8) | 0.98 | 0.44-2.17 | 13 (13.3) | 2.51* | 1.21-5.18 | 18 (12.0) | 2.65* | 1.42-4.96 |
(univariate effects)
|
1.22
|
0.57-2.64
|
4.80*
|
2.48-9.28
|
4.28*
|
2.39-7.64
| ||||
T1 Socio-demographics
| ||||||||||
Girl | 747 (55.0) | 66 (31.0) | 0.41* | 0.30-0.56 | 40 (40.8) | 0.64* | 0.41-1.00 | 72 (48.0) | 0.84 | 0.59-1.20 |
(univariate effects)
|
0.37*
|
0.27-0.50
|
0.57*
|
0.37-0.56
|
0.76
|
0.54-1.06
| ||||
Non-western immigrant | 87 (6.4) | 23 (10.8) | 1.66 | 1.00-2.76 | 23 (23.5) | 3.11* | 1.76-5.47 | 29 (19.3) | 2.67* | 1.62-4.39 |
(univariate effects)
|
1.77*
|
1.09-2.87
|
4.48*
|
2.68-7.51
|
3.50*
|
2.21-5.55
| ||||
Parents divorced | 248 (18.2) | 33 (26.8) | 1.45 | 0.99-2.12 | 33 (33.7) | 1.47 | 0.88-2.47 | 32 (21.3) | 0.81 | 0.51-1.31 |
(univariate effects)
|
1.64*
|
1.17-2.28
|
2.27*
|
1.46-3.54
|
1.22
|
0.80-1.84
| ||||
Lower educ.mother (≤lower tracks of sec. educ.) | 422 (31.1) | 88 (41.3) | 1.30 | 0.94-1.78 | 60 (61.2) | 2.24* | 1.42-3.54 | 88 (58.7) | 2.52* | 1.75-3.64 |
(univariate effects)
|
1.56*
|
1.16-2.10
|
3.51*
|
2.30-5.35
|
3.15*
|
2.23-4.45
| ||||
Low family income (<€1,135) | 157 (11.6) | 40 (18.8) | 1.23 | 0.78-1.92 | 34 (34.7) | 1.88* | 1.09-3.24 | 38 (25.3) | 1.63* | 1.01-2.64 |
(univariate effects)
|
1.77*
|
1.21-2.60
|
4.07*
|
2.60-6.37
|
2.60*
|
1.74-3.89
| ||||
Low IQ (wisc < 85) | 180 (13.2) | 44 (20.7) | 1.43 | 0.96-2.12 | 37 (37.8) | 2.27* | 1.40-3.67 | 39 (26.0) | 1.43 | 0.93-2.20 |
(univariate effects)
|
1.71*
|
1.18-2.46
|
3.97*
|
2.57-6.15
|
2.30*
|
1.55-3.42
| ||||
T1 Psycho-pathology
| mean (SD) | mean (SD) | OR | 95% CI | mean (SD) | OR | 95% CI | mean (SD) | OR | 95% CI |
CBCL Int | 0.25 (0.19) | 0.24 (0.21) | 0.81* | 0.67-0.98 | 0.25 (0.20) | 0.75* | 0.58-0.97 | 0.26 (0.21) | 0.96 | 0.78-1.18 |
(univariate effects)
|
0.97
|
0.84-1.12
|
1.00
|
0.81-1.23
|
1.09
|
0.92-1.28
| ||||
CBCL Ext | 0.22 (0.19) | 0.29 (0.21) | 1.38* | 1.17-1.62 | 0.31 (0.27) | 1.43* | 1.14-1.79 | 0.29 (0.24) | 1.29* | 1.06-1.56 |
(univariate effects)
|
1.38*
|
1.21-1.57
|
1.48*
|
1.24-1.76
|
1.34*
|
1.15-1.57
| ||||
YSR Int | 0.37 (0.24) | 0.33 (0.21) | 0.88 | 0.75-1.03 | 0.36 (0.25) | 0.88 | 0.71-1.10 | 0.33 (0.24) | 0.77* | 0.64-0.94 |
(univariate effects)
|
0.85*
|
0.73-0.99
|
0.96
|
0.78-1.17
|
0.85
|
0.71-1.02
|