Growing up in Scotland: children's social, emotional and behavioural characteristics at entry to primary school

APPENDIX 2 - FURTHER DETAILS OF EXPLANATORY AND OUTCOME VARIABLES

Strengths and Difficulties Questionnaire - Normal, Borderline and Abnormal score bandings for parent-completed version

Family type transitions

Using information on family type (couple family or lone parent household) collected at every sweep, a variable was constructed which measured stability or changes in family type between the ages of 2 and 5 (sweeps 1 to 4). Four classifications were derived: stable couple family, couple who separate, stable lone parent and lone parent who repartnered.

Equivalised annual household income

The income that a household needs to attain a given standard of living will depend on its size and composition. For example, a couple with dependent children will need a higher income than a single person with no children to attain the same material living standards. "Equivalisation" means adjusting a household's income for size and composition so that we can look at the incomes of all households on a comparable basis.

Children's general health

At each sweep of fieldwork, parents are asked to rate their child's general health on a five-point scale ranging from very good through to very bad. The measure used in this report captures changes in child's health status between the ages of 2 and 5 (sweeps 2 to 4). Children who were reported to have fair, bad or very bad health at any or all time points were categorized as temporarily or always having fair, bad or very bad health.

Delays in motor development

Developmental milestones are a set of functional skills or age-specific tasks that most children can do at a certain age range. Although each milestone has an age level, the actual age when a normally developing child reaches that milestone can vary considerably. For example, some children may walk as early as 11 months, while others may not
walk until they are 15 months old. Both cases are still considered normal. Statistically speaking about 3% of children will not reach a milestone on time, but most of them will eventually develop normally over time, although a little later than expected.

The milestones were assessed by main respondents' reports on their child's developmental status at age 2 (34 months), using 14 items derived from the Denver Development Screening Test and which covered gross and fine motor skills. For each item, the respondent was asked to indicate whether or not the child could perform the action.

The actions included are:

• Walk on the level without difficulties
• Walk up steps like an adult, one foot on each step
• Balance on one foot for at least four seconds
• Hop at least twice on one foot
• Throw a ball
• Grasp and handle small objects such as a pencil and scissors
• Undo big buttons
• Draw a circle
• Hold a pencil and scribble
• Copy a square
• Drink from a cup
• Brush his/her teeth without help at least some of the time
• Put on a T-shirt by him/herself
• Get dressed without any help

Negative responses on each item were counted and a variable was constructed which indicated whether the child, at 34 months, had not yet reached any milestones. Categories on this variable were none (indicating the child had reached all milestones), 1, 2, or 3 or more.

Language difficulties at age 2

Difficulties with the child's speech and language at age 2 was measured through a set of three questions included at sweep 1 where the main respondent was asked to assess the extent to which the child could be understood when speaking by the respondent, by other friends and family, and by strangers. The available responses were 'mostly', 'sometimes' and 'rarely'. The variable used in this report combined data from across the three items to a binary variable indicating any difficulties with the child's speech being understood. Children who were said to be only sometimes or rarely understood on any of the three items were categorised as having some language difficulties.

Harsh discipline

At age 3 (46 months, sweep 2), parents were asked the extent to which they had ever used a range of discipline approaches with the cohort child. The approaches included were:

• Time out
• Reward system/sticker chart
• Ignoring bad behaviour
• Smacking
• Naughty step/room/corner
• Raising your voice or shouting
• Removing treats or privileges

Responses to the items on smacking and shouting were combined to create a single variable indicating whether any or both of these approaches had been used.

Parent-child social interaction

Parent-child social interaction at age 3 (46 months, sweep 2) was measured using four items which asked the main respondent how frequently they talked to, read to, played with, and cuddled the cohort child. The 5-item response set ranged from 'less than once a week' to 'more than once a day'. Responses were recoded, standardised and combined into a single scale. A high score on the scale indicated a high frequency of parent-child social interaction.

Frequency child taken to visit other people with children at age 2

This variable was derived from a question included at sweep 1 (age 34 months) which asked how often the main respondent or his/her partner took the child to visit friends with young children. Responses were on a 9-point scale from 'Every day/most days' to 'Never'. The data was recoded to separate out children who experienced this kind of social visit at least fortnightly and those who did so less often.