Background
Methods
Design, setting, and data source
Primary outcome and exposures
Potential confounding factors
Early life risk factors (potential mediators)
Factors that may influence environmental safety
Factors that may influence child supervision
Child’s abilities and behaviours
Analysis strategy and statistical methods
Sensitivity analyses
Results
Variables | Income quintile | Total | P-valueb | ||||
---|---|---|---|---|---|---|---|
First (Highest) | Second | Third | Fourth | Fifth (lowest) | Percent (count) | ||
Count of child in each quintile
|
2490
|
2695
|
2771
|
3138
|
3261
|
14,553
| – |
Unintentional injuries between 3 and 5 years old | 24.0 | 26.9 | 28.7 | 29.4 | 31.0 | 28.0 (4019) | < 0.001 |
Baseline Risks | |||||||
MCS child (MCSc) is male, recorded at 9 months old | 51.3 | 50.7 | 51.7 | 50.8 | 50.4 | 51.0 (7335) | 0.09 |
MCSc from non-white ethnic group recorded at 9 months old | 8.0 | 5.5 | 8.5 | 16.6 | 23.4 | 12.1 (1919) | < 0.001 |
Maternal age at birth, recorded at 9 months old | |||||||
14–19 years | 0.5 | 1.5 | 4.2 | 9.0 | 23.1 | 7.7 (1114) | < 0.001 |
20–24 years | 3.0 | 8.3 | 16.8 | 25.8 | 29.1 | 16.6 (2551) | |
25–34 years | 94.6 | 88.6 | 78.2 | 64.0 | 46.8 | 74.4 (10494) | |
35+ years | 2.0 | 1.6 | 0.8 | 1.3 | 1.0 | 1.3 (195) | |
Number of children in the household at birth (including MCSc) recorded at 9 months old | |||||||
MCS lone child | 56.8 | 43.0 | 40.0 | 31.6 | 39.4 | 42.1 (6008) | < 0.001 |
2/3 children | 41.1 | 54.3 | 54.8 | 56.5 | 47.9 | 50.9 (7226) | |
4 or more children | 2.2 | 2.7 | 5.3 | 11.9 | 12.7 | 7.0 (1121) | |
Factors That May Influence Environmental Safety | |||||||
No safe areas to play, MCSc 9 months old | 20.4 | 25.4 | 34.1 | 43.0 | 51.0 | 34.8 (5367) | < 0.001 |
Items of named safety equipment used, MCSc 9 months old (count)a | |||||||
None | 0.4 | 0.4 | 0.7 | 3.5 | 7.6 | 2.5 (452) | < 0.001 |
1 piece | 3.5 | 3.8 | 5.6 | 11.4 | 17.6 | 8.4 (1280) | |
2 pieces | 18.8 | 17.6 | 19.8 | 22.7 | 25.4 | 20.9 (3081) | |
3 pieces | 25.9 | 25.3 | 26.6 | 26.1 | 23.8 | 25.6 (3739) | |
4 pieces | 31.0 | 33.4 | 31.2 | 23.8 | 17.3 | 27.4 (3724) | |
5 pieces | 20.3 | 19.6 | 16.1 | 12.4 | 8.2 | 15.3 (2075) | |
No garden, MCSc age 3 | 1.5 | 2.3 | 4.1 | 9.8 | 17.0 | 6.7 (873) | < 0.001 |
Type of childcare used, MCSc age 3 | |||||||
Parent care only | 47.8 | 56.2 | 67.0 | 84.6 | 93.5 | 69.2 (8858) | < 0.001 |
Registered childcare (e.g. Ofsted inspected nursery) | 19.0 | 26.2 | 24.9 | 12.4 | 5.1 | 17.8 (2479) | |
Non-registered childcare (e.g. family, friends) | 33.2 | 17.6 | 8.1 | 3.1 | 1.4 | 13.0 (1575) | |
Has a household pets, MCSc age 3 | 42.5 | 50.8 | 54.8 | 51.8 | 45.8 | 49.1 (6029) | < 0.001 |
Poor home safety (HOME score), MCSc age 3 | 0.1 | 1.1 | 0.9 | 2.3 | 3.8 | 1.6 (191) | < 0.001 |
Exposed to household smoking, MCSc age 3 | 5.2 | 6.9 | 13.3 | 24.5 | 36.8 | 16.9 (2217) | < 0.001 |
Responder feels unsafe in area, MCSc age 3 | 5.4 | 5.6 | 10.3 | 17.0 | 23.0 | 12.0 (1656) | < 0.001 |
Disorganised home environment, MCSc age 3 | |||||||
Very organised | 25.0 | 22.3 | 19.3 | 17.4 | 15.8 | 20.1 (2608) | < 0.001 |
Organised | 57.2 | 56.5 | 55.6 | 50.5 | 48.2 | 53.7 (6967) | |
Average | 10.2 | 11.4 | 13.5 | 15.5 | 16.3 | 13.3 (1668) | |
Disorganised | 6.3 | 8.6 | 10.0 | 13.7 | 16.2 | 10.8 (1379) | |
Very disorganised | 1.3 | 1.2 | 1.6 | 2.9 | 3.5 | 2.1 (261) | |
Factors that may influence supervision | |||||||
Primary carer distressed, MCSc age 3 | 0.7 | 1.0 | 2.2 | 3.4 | 5.9 | 2.5 (302) | < 0.001 |
Primary carer Limiting long term condition, MCSc age 3 | 15.9 | 18.5 | 22.0 | 26.6 | 25.4 | 21.51 (2841) | < 0.001 |
Primary caregiver alcohol units per week, MCSc age 3 | |||||||
None | 34.5 | 49.9 | 62.0 | 71.5 | 76.3 | 58.9 (8947) | < 0.001 |
1–6 units | 43.7 | 36.2 | 28.2 | 19.7 | 14.5 | 28.4 (3735) | |
7–14 units | 18.2 | 11.4 | 8.0 | 6.8 | 6.3 | 10.1 (1349) | |
15 or more units (exceeding current UK Guidance) | 3.6 | 2.5 | 1.8 | 1.9 | 2.9 | 2.5 (317) | |
Has an unstructured parenting style (e.g. few rules) MCSc age 3 | 45.3 | 49.4 | 57.3 | 61.9 | 65.3 | 55.5 (7068) | < 0.001 |
Family and friends live nearby MCSc age 3 | |||||||
Both | 40.0 | 50.8 | 55.8 | 52.5 | 50.7 | 50.0 (7285) | < 0.001 |
Family only | 5.0 | 6.8 | 8.8 | 9.6 | 12.4 | 8.5 (1350) | |
Friends only | 40.3 | 30.6 | 23.8 | 23.7 | 21.3 | 27.9 (3796) | |
Neither nearby | 14.7 | 11.8 | 11.6 | 14.3 | 15.6 | 13.6 (1906) | |
Factors relating to the mcs child’s abilities and behaviours | |||||||
Score from Strength and Difficulties Questionnaire (SDQ) MCSc age 3, graded as: | |||||||
Average | 90.0 | 88.6 | 81.1 | 72.8 | 63.6 | 79.9 (9607) | < 0.001 |
Borderline | 6.4 | 7.4 | 11.0 | 12.5 | 14.9 | 10.2 (1258) | |
Below average | 3.7 | 4.1 | 7.9 | 14.7 | 21.6 | 9.9 (1248) | |
Sight concerns, MCSc age 3 | 5.1 | 5.8 | 6.4 | 6.0 | 6.1 | 5.9 (566) | 0.19 |
Hearing concerns, MCSc age 3 | 5.4 | 4.0 | 4.2 | 4.2 | 4.0 | 4.3 (853) | 0.52 |
Child is NOT school ready, MCSc age 3 | 3.5 | 5.3 | 9.4 | 18.2 | 26.5 | 12.1 (1586) | < 0.001 |
Variables | Total sample (n = 14,355)a | FINAL MODEL COMPLETE CASE (n = 10,210)b | |||||
---|---|---|---|---|---|---|---|
Univariable | Multivariable | ||||||
Risk ratio (RR) | 95% LCI | 95% UCI | P-value | RR | 95% LCI | 95% UCI | |
Household Income Quintiles | |||||||
First (refer: highest) | Ref | – | – | < 0.001 | Ref | – | – |
Second | 1.12 | 0.99 | 1.25 | 1.08 | 0.96 | 1.22 | |
Third | 1.19 | 1.06 | 1.33 | 1.11 | 0.98 | 1.26 | |
Fourth | 1.22 | 1.07 | 1.38 | 1.09 | 0.95 | 1.26 | |
Fifth (Lowest) | 1.27 | 1.13 | 1.43 | 1.15 | 0.996 | 1.34 | |
Baseline Risk Factors | |||||||
Child’s sex (Ref: female) | 1.22 | 1.14 | 1.31 | < 0.001 | 1.22 | 1.13 | 1.32 |
Child ethnic group (Ref: White) | 0.74 | 0.66 | 0.82 | < 0.001 | 0.79 | 0.68 | 0.91 |
Maternal age at MCS birth | |||||||
35+ years | Ref | – | – | < 0.001 | Ref | – | – |
25–34 years | 0.69 | 0.5 | 0.93 | 1.07 | 0.92 | 1.25 | |
20–24 years | 0.84 | 0.76 | 0.93 | 0.95 | 0.82 | 1.11 | |
14–19 years | 0.99 | 0.88 | 1.11 | 0.77 | 0.55 | 1.09 | |
Number of children in the household at birth (including MCS child) | |||||||
MCS lone child | Ref | – | – | 0.01 | Ref | – | – |
2/3 children | 1.1 | 1.03 | 1.17 | 1.10 | 1.01 | 1.20 | |
4 or more children | 1.11 | 0.99 | 1.25 | 1.22 | 1.04 | 1.44 | |
Factors That May Influence Environmental Safety | |||||||
Safe areas to play at home at 9 months (Ref: No safe areas) | 1.06 | 0.99 | 1.12 | 0.08 | 1.00 | 0.92 | 1.08 |
Items of named safety equipment used at 9 months | |||||||
None | Ref | – | – | 0.04 | Ref | – | – |
1 piece | 1.13 | 0.87 | 1.47 | 1.15 | 0.79 | 1.66 | |
2 pieces | 1.28 | 1.01 | 1.63 | 1.25 | 0.9 | 1.74 | |
3 pieces | 1.32 | 1.04 | 1.67 | 1.36 | 0.98 | 1.89 | |
4 pieces | 1.34 | 1.06 | 1.7 | 1.36 | 0.98 | 1.90 | |
5 pieces | 1.33 | 1.04 | 1.71 | 1.36 | 0.97 | 1.92 | |
Access to a garden at 9 months (Ref: No access) | 1.05 | 0.91 | 1.21 | 0.49 | – | – | – |
Type of childcare used MCSc age 3 | |||||||
None (parents look after child) | Ref | – | – | 0.09 | Ref | – | – |
Registered childcare provider | 0.91 | 0.83 | 1 | 0.99 | 0.89 | 1.10 | |
Non-registered childcare provider (e.g. family, friends) | 0.94 | 0.85 | 1.04 | 1.03 | 0.91 | 1.17 | |
Household pets MCSc age 3 (ref: No pets) | 1.14 | 1.07 | 1.21 | < 0.001 | 1.04 | 0.97 | 1.12 |
Household smoking MCSc age 3 (ref: None) | 1.15 | 1.05 | 1.26 | < 0.001 | 1.01 | 0.90 | 1.13 |
Poor home safety (HOME score) MCSc age 3 | 1.20 | 0.93 | 1.55 | 0.17 | – | – | – |
Responder feels unsafe in area MCSc age 3 | 1.12 | 1.03 | 1.22 | 0.01 | 1.08 | 0.98 | 1.19 |
Disorganised home environment MCSc age 3 | |||||||
Very organised | Ref | – | – | < 0.001 | Ref | – | – |
Organised | 1.09 | 1 | 1.18 | 1.05 | 0.95 | 1.15 | |
Average | 1.15 | 1.02 | 1.29 | 1.11 | 0.98 | 1.27 | |
Disorganised | 1.16 | 1.02 | 1.31 | 1.06 | 0.92 | 1.22 | |
Very disorganised | 1.61 | 1.32 | 1.95 | 1.35 | 1.09 | 1.67 | |
Factors That May Influence Supervision | |||||||
Maternal distress at 3 yrs. (Ref: Kessler < 5) | 1.33 | 1.12 | 1.59 | 0.01 | 1.18 | 0.94 | 1.47 |
Limiting long term condition MCSc age 3 (Ref: none) | 1.16 | 1.07 | 1.26 | < 0.001 | 1.08 | 0.98 | 1.19 |
Alcohol units per week (MCSc age 3) | |||||||
None | Ref | – | – | 0.58 | – | – | – |
1–6 units | 0.98 | 0.92 | 1.05 | – | – | – | |
7–14 units | 1.04 | 0.93 | 1.16 | – | – | – | |
15 or more units+ | 1.1 | 0.92 | 1.32 | – | – | – | |
Approach to parenting MCSc age 3 (Ref: Unstructured) | 1 | 0.93 | 1.06 | 0.71 | – | – | – |
Family and friends live nearby, MCSc age 3 (Ref: both) | |||||||
Both | Ref | – | – | 0.19 | – | – | – |
Family only | 1.06 | 0.95 | 1.17 | – | – | – | |
Friends only | 0.95 | 0.89 | 1.02 | – | – | – | |
Neither nearby | 1.00 | 0.91 | 1.11 | – | – | – | |
Factors Relating To The Mcs Child’s Abilities And Behaviours | |||||||
Strength and Difficulties Questionnaire (SDQ), MCSc age 3 | |||||||
Average | Ref | – | – | < 0.001 | Ref | – | – |
Borderline | 0.06 | 1.03 | 1.26 | 1.05 | 0.93 | 1.19 | |
Below average | 1.32 | 1.19 | 1.46 | 1.16 | 1.03 | 1.32 | |
Sight concerns, MCSc age 3 | 1.02 | 0.9 | 1.15 | 0.75 | – | – | – |
Hearing concerns, MCSc age 3 | 1.08 | 0.95 | 1.23 | 0.24 | – | – | – |
Child is NOT school ready, MCSc age 3 | 0.91 | 0.82 | 1.00 | 0.06 | 1.06 | 0.96 | 1.18 |