Publication - Research and analysis

Growing up in Scotland: the impact of children's early activities on cognitive development

Published: 18 Mar 2009
Directorate:
Children and Families Directorate
Part of:
Children and families, Education
ISBN:
9780755919680

This report uses data from the first three waves of the Growing Up in Scotland study (GUS) to explore children’s cognitive ability.

92 page PDF

1.8 MB

92 page PDF

1.8 MB

Contents
Growing up in Scotland: the impact of children's early activities on cognitive development
Chapter 4 Factors Influencing Cognitive Development

92 page PDF

1.8 MB

Chapter 4 Factors Influencing Cognitive Development

4.1 Key findings

  • Cognitive ability was measured in children at age 34 months using assessments of their language development (naming vocabulary) and problem solving skills (picture similarities).
  • Large variations in cognitive scores were evident at age 34 months with children from less advantaged families outperformed by their more affluent counterparts on both assessments.
  • Children who had been identified at 22 months as having developmental difficulties had lower cognitive ability scores than children with no developmental difficulties. Children born with low birth weight and boys also had lower than average ability scores.
  • Children whose mothers have no qualifications scored less well than those with degree-educated mothers (who perform particularly well, especially on the naming vocabulary assessment). Children with older mothers (30 years or above) perform better than those with younger mothers.
  • Children in households with four or more children have lower ability scores than those with fewer or no siblings. Low household income levels and unemployment/low working hours are also significant factors associated with poorer performance.
  • Those in the 15% most deprived areas of Scotland have lower scores than those in the rest of Scotland.
  • Children who were read to often, and those who had visited a library by the time they were 10 months old, scored higher on both assessments than children who had comparably less experience of these activities (though the impact was less pronounced for the picture similarities assessment than for the naming vocabulary).
  • At age 22 months the number of days in the past week children had played educational games, their overall daily activity levels and the number of places or events they had visited in the past year were all associated with cognitive ability. The more activities children had experienced the higher their ability scores.
  • Ability scores were higher among children whose parents rated four or five activities as very important, and whose parents were satisfied with the range of their activities, than for children whose parents attached less importance to activities or were dissatisfied with their range.
  • The association between activity levels and cognitive ability might simply be a reflection of the fact that children with high activity levels tend to be from more socially advantaged backgrounds; this is explored further in the next chapter.

4.2 Introduction

This chapter looks at variations in cognitive ability scores across a number of different socio-demographic factors as well as the activities measures outlined in the previous chapter. The intention here is to present an overview of interesting patterns of association based on a selection of factors, rather than to provide an exhaustive exploration of cognitive ability. All of the factors presented below will be considered further in the next chapter where the question of how these all inter-relate will be addressed.

4.3 Socio-demographic factors

The socio-demographic factors considered in this analysis can be classified into four types:

  • Child level factors:
  • Birth weight
  • Gender
  • Developmental difficulties identified at 22 months
  • Mother level factors:
  • Age at birth
  • Education level
  • Household level factors:
  • Number of children in household
  • Equivalised income
  • Family and employment type
  • Area level:
  • Scottish index of multiple deprivation

Not only are the above factors strongly associated with activities, as shown in Chapter 3, they are also strongly related to each other. This is explored in the next chapter.

The most striking point to note from all the tables presented below is the extent to which large variations in ability are evident from a very early point in life. At just 34 months of age children from less advantaged families are outperformed by their more affluent counterparts on both the measures (naming vocabulary and picture similarities). Although individual differences in performance are shaped by a vast and complex range of factors, including many genetic or biological factors which are beyond the scope of being captured in a study like GUS, there is compelling evidence that social environment is a hugely critical determinant of outcomes. The implications of this in terms of appropriate policy interventions, and the likely impact that these early developmental differences might have on these children's outcomes later in life, are not insignificant.

4.3.1 Child level factors

Table 4.1 presents the mean T-scores 3 for both ability measures and how they vary by birth weight, gender and whether the child was identified as having some developmental difficulties at age 22 months. This latter measure is based on the Infant-Toddler Checklist component of the Communication and Symbolic Behaviour Scales ( CSBS) 4 that was administered at sweep 2. This identifies children whose communication development is of concern, for example that they are not using the kinds of language or gestures expected of a child of their age. The strength of association with both cognitive ability scores is notable - children identified at 22 months as being of concern have much lower scores than children for whom no concerns were identified. This suggests that the CSBS assessment has been a useful tool within GUS for identifying children at risk of later developmental problems. Although they constitute a relatively small group within the population overall, they are an interesting group whose later outcomes are worth monitoring as they age. In addition, as the number of cognitive and developmental assessments carried out in GUS increases over time it might be possible to identify children whose developmental indicators suggest persistent concern and look at the risk factors associated with this status.

The finding that ability scores are lower for boys and those with low birth weights is consistent with evidence from previous studies (as already discussed in section 2.4).

Table 4.1 Average cognitive ability T-scores at age 34 months by child level factors

Socio- demographic factors

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Birth weight

Low

48.1

256

233

Not low

51.9

3594

3648

Gender

Boy

49.3

1990

1995

Girl

54.0

1928

1954

Developmental difficulties at 22 months

Some difficulties identified

44.0

262

248

No difficulties

52.5

3284

3341

Picture similarities**

Birth weight

Low

46.5

256

233

Not low

49.9

3593

3646

Gender

Boy

48.6

1990

1994

Girl

50.8

1927

1953

Developmental difficulties at 22 months

Some difficulties identified

45.4

262

248

No difficulties

50.1

3284

3339

**Differences significant at less than .001

4.3.2 Mother level factors

Turning now to look at factors related to the children's mothers shows that both age and education are associated with ability scores. Children whose mothers have no qualifications scored less well than those with degree-educated mothers who appeared to perform particularly well, especially in respect of the naming vocabulary scores. Having an older mother (30 years or above) also appeared to confer an advantage.

Table 4.2 Average cognitive ability T-scores at age 34 months by mother level factors

Socio- demographic factors

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Mother's highest educational qualification

Degree

55.5

1091

1245

Vocational below degree

51.2

1489

1513

Higher grade

51.3

306

315

Standard grade

49.6

688

602

No qualifications

45.6

332

263

Mother's age at birth

Under 20

47.5

294

202

20 to 29

49.9

1582

1461

30 to 39

53.6

1888

2117

40+

54.4

128

147

Picture similarities**

Mother's highest educational

qualification

Degree

52.1

1090

1244

Vocational below degree

49.8

1487

1512

Higher grade

50.0

306

315

Standard grade

47.9

688

602

No qualifications

44.8

332

263

Mother's age at birth

Under 20

45.9

294

202

20 to 29

48.9

1582

1461

30 to 39

51.0

1887

2115

40+

49.9

128

147

**Differences significant at less than .001

4.3.3 Household level factors

The household level factors include a measure of income that has been adjusted to take account of the household size, employment patterns (which can also be a proxy measure of income), and a measure of the total number of children in the family. This latter measure will in part reflect the way in which financial resources are spread within a household, with costs rising as family size increases, but it is also a useful measure of the possible distribution of time resources within a family. One possible hypothesis is that children in large families spend proportionately less time interacting with their parents than children in smaller units. Alternatively, it is possible that the greater opportunity for sibling interactions in larger households confers a developmental advantage on children in such families. Table 4.3 suggests that children in households with four or more children have lower ability scores than those with fewer or no siblings, and that low income levels and unemployment/low working hours are also significant factors associated with poor performance. However, larger family sizes are also commonly associated with lower income households so the analysis will need to be taken a little further to untangle the patterns evident here. The next chapter addresses this.

Table 4.3 Average cognitive ability T-scores at age 34 months by household level factors

Socio- demographic factors

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Number of children in household

One

53.2

1326

1289

Two

51.9

1764

1841

Three

49.2

631

637

Four or more

46.4

198

182

Equivalised household income quintile

Up to £8,409

46.0

871

719

£8,410-13,749

50.5

785

761

£13,750-21,784

53.0

685

723

£21,785-33,570

54.6

742

820

£33,571 and above

56.0

604

693

Income unknown

51.8

231

233

Family and employment type

Lone parent working >16 hours

51.1

304

272

Lone parent unemployed/working <16 hours

45.6

440

339

Couple both working >16 hours

54.3

1712

1863

Couple one person working >16 hours

51.1

1291

1330

Couple both unemployed/working <16 hours

45.2

161

134

Number of children in household

One

50.3

1325

1289

Two

50.2

1763

1839

Three

48.1

631

637

Four or more

46.8

198

182

Equivalised household income quintile

Up to £8,409

45.5

870

718

£8,410-13,749

49.4

785

761

£13,750-21,784

50.3

685

722

£21,785-33,570

51.9

741

819

£33,571 and above

52.7

605

699

Income unknown

50.0

231

233

Family and employment type

Lone parent working >16 hours

50.2

304

272

Lone parent unemployed/working <16 hours

44.3

439

338

Couple both working >16 hours

51.2

1712

1863

Couple one person working >16 hours

50.1

1290

1329

Couple both unemployed/working <16 hours

44.7

161

134

**Differences significant at less than .001

4.3.4 Area deprivation

This final socio-demographic indicator uses a neighbourhood level measure of deprivation so goes beyond the confines of individual or household circumstances. Table 4.4 compares the scores of children living in the 15% most deprived of areas in Scotland with those in the rest of the country. For both assessments children in the 15% most deprived areas have lower scores than those in the rest of Scotland.

Table 4.4 Average cognitive ability T-scores at age 34 months by Scottish Index of Multiple Deprivation

Socio-demographic factors

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Scottish Index of Multiple Deprivation

15% most deprived areas

48.2

662

534

Rest of Scotland

52.3

3257

3415

Picture similarities**

Scottish Index of Multiple Deprivation

15% most deprived areas

46.0

660

533

Rest of Scotland

50.5

3256

3414

**Differences significant at less than .001

4.4 Children's activities

The reasoning behind the selection of the following activities is set out in Chapter 3 and will not be repeated here. However, a reminder of the measures being explored is useful:

  • Activities at age 10 months
  • Frequency of reading with the child
  • Whether the child ever visits the library
  • Activities at age 22 months
  • Number of days in the past week the child had played educational games (recognising shapes, numbers, letters)
  • Overall daily activity levels in past week (composite measure based on 5 activities, in quartiles)
  • Number of different places/events child had been to in past year
  • Parental attitudes at 22 months
  • Parent's perceptions of the importance of playing educational games
  • Number of activities parents rated as very important for their child to do
  • Parental satisfaction levels with child's range of activities

As was the case with the socio-demographic factors discussed above, the patterns of association between activities, parental views and cognitive ability scores are striking. However, a similar - or indeed stronger - note of caution needs to be flagged here in terms of what these results do and do not mean. While it is very evident that ability scores increase in line with rising activity levels, there is not sufficient proof that one causes the other. The results presented below are only part of the investigation into why children's outcomes differ so markedly, the discussion in the next chapter expands on this and goes further by identifying the influence these activity measures have once other socio-demographic factors have been taken into consideration. This section should not, therefore, be read in isolation without reference to the analysis still to come. With this in mind the following commentary simply highlights the key findings from the tables and does not go into extensive detail about their possible implications.

4.4.1 Activities at 10 months

Both measures of early 'literary' activity show an association with ability scores, with children who were read to often, and those who had visited a library by the time they were 10 months old, scoring higher on both assessments than children who had comparably less experience of these activities. Although statistically significant, the absolute size of the difference between the picture similarity scores for children who had been to a library and those who had not is actually quite small so its overall impact is probably marginal. This type of finding is common in studies with large samples such as GUS.

Table 4.5 Average cognitive ability T-scores at age 34 months by activities at 10 months

Activities at 10 months

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Frequency of reading/looking at books with child

Every day

53.0

2560

2653

Once or twice a week

50.5

790

772

Once every one or two months or less

47.7

277

258

Never

45.1

225

201

Whether child ever visits library

Has been

53.5

1003

1079

Has never been

51.0

2848

2803

Picture similarities**

Frequency of reading/looking at books with child***

Every day

50.5

2558

2653

Once or twice a week

48.6

790

772

Once every one or two months or less

48.1

277

258

Never

45.5

225

201

Whether child ever visits library

Has been

50.6

1002

1077

Has never been

49.3

2848

2803

**Differences significant at less than .001

4.4.2 Activities at 22 months

All three activity measures at 22 months show significant associations with ability scores and the magnitude of the differences between groups is also quite notable. For example, the mean naming vocabulary t-score for the 25% most active children (based on their activities in the previous week) is 56.0 compared with 45.1 for children in the 25% least active group.

Table 4.6 Average cognitive ability T-scores at age 34 months by activities at 22 months

Activities at 22 months

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

No. of days child played educational games in past

week

Every day

53.8

1138

1149

Four-six days

53.6

528

541

One to three days

51.5

971

986

None

48.9

1204

1196

Overall daily activity level quartile

First quartile (most active 25%)

56.0

895

932

Second quartile

53.1

1112

1136

Third quartile

51.2

1068

1093

Fourth quartile (least active 25%)

45.1

760

706

Number of different places/events visited in past year

Five or more

55.3

725

814

Four

53.9

799

849

Three

51.5

983

993

Two

50.0

840

790

None/one

45.9

507

438

No. of days child played educational games in past week

Every day

50.7

1139

1150

Four-six days

51.0

528

541

One to three days

49.5

970

985

None

48.3

1202

1194

Overall daily activity level quartile

First quartile (most active 25%)

52.1

896

933

Second quartile

50.8

1110

1134

Third quartile

49.3

1067

1092

Fourth quartile (least active 25%)

45.9

760

706

Number of different places/events visited in past year

Five or more

52.1

723

812

Four

51.2

800

850

Three

49.8

983

993

Two

48.1

838

789

None/one

46.1

507

438

**Differences significant at less than .001

4.4.3 Parental attitudes towards, and satisfaction with, activities at 22 months

Table 4.7 looks at parent's assessments of the importance of activities and their satisfaction with their children's range of activities. While the item measuring the importance of reading and educational games is of substantive interest, given its high correspondence with the kinds of abilities assessed in these two cognitive tests, it is a less useful discriminator of views than the composite measure of broader views about the importance of activities. This is unsurprising as a very high proportion of parents rated educational games as very important. Nevertheless, even amongst those who said this was important the degree of importance they attached to it (very or quite) was correlated with ability scores.

Table 4.7 Average cognitive ability T-scores at age 34 months by parental attitudes at 22 months

Parental attitudes

Mean score

Bases

Naming vocabulary**

Weighted

Unweighted

Importance of playing educational games/reading with child +

Very important

52.5

3198

3263

Quite important

47.5

598

574

No. of activities rated as important

Four or five

53.5

1958

2026

Three

51.7

933

957

Two

48.9

514

495

One or none

46.7

442

402

Satisfaction with child's activities

Very happy

53.3

736

794

Quite happy

52.7

1431

1478

Would like a slightly wider range

50.6

1048

1032

Would like a much wider range

49.1

594

538

Picture similarities**

Importance of playing educational games/reading with child +

Very important

50.3

3197

3261

Quite important

47.1

598

574

No. of activities rated as important

Four or five

50.8

1957

2024

Three

49.5

934

958

Two

49.0

513

494

One or none

46.0

442

402

Satisfaction with child's activities

Very happy

51.3

736

794

Quite happy

49.8

1430

1476

Would like a slightly wider range

49.2

1048

1032

Would like a much wider range 48.3 593 538

+The sample sizes for the rest of categories are too small to report

**Differences significant at less than .001

4.5 Conclusion

This chapter has provided an overview of the relationship between cognitive ability and socio-demographic factors and children's activities. The results confirm much of what the existing literature suggests about the kinds of factors that influence cognitive outcomes. For example, children's individual characteristics such as their gender, birth weight and developmental history are all associated with their cognitive ability at age 34 months with boys, low birth weight babies and children who had experienced developmental difficulties in the first year of life all found to have below average ability scores. Children whose mothers were aged under 20 when they were born or who have low levels of educational achievement (two factors that are themselves strongly linked) also performed below the average. Household and area level indicators of disadvantage, such as low income, unemployment or area deprivation also showed negative associations with ability scores. The range of activity measures defined in the previous chapter were also found to be associated with cognitive ability; children who experience a wide range of activities and those whose parents consider this to be important had higher than average ability scores. Whether the fact that children from more advantaged backgrounds also experience more activities is the underlying explanation for this apparent association between activities and cognitive outcomes remains to be seen. The next chapter aims to untangle this.