Data cleaning and sample profile

As with previous years, measures of placement stability are derived from the Children Looked After Census and relate to the cohort of children in care at 31st March. Table 1 demonstrates the profile of this sample.

Table 1: Profile of children in care at 31st March 2018. N = 75420

For our purposes a change in placement is a change in a child’s carer during their time in care. This includes any re-entries into care during the relevant time period, however for children not in care at the start of the time period, we exclude their first entry into care. Clearly some of these changes of carer may be for good reasons however it is not possible within the CLA census to define or identify changes that are ‘good’ or ‘bad’. For consistency with national statistics published by the Department for Education (DfE), we have also excluded any episodes of respite care from our counts.

Similar caveats with this sample apply as with last year’s, namely that:

• Not all children in our sample are in care for the whole of 2017/18. In total, 23,060 children (31% of the sample) were not in care throughout 2017/18. They therefore had less time in care during which they could experience placement moves, compared to those in care continuously for at least 12 months.

• Similarly when looking at instability over the longer term, not all children will have been in care continuously over the required time period. For these individuals, therefore, measures of longer term placement instability cannot be defined. The samples are therefore restricted to children in care for at least one day during the first and last year of the relevant time period. For example measures looking at a child’s instability over a two-year period are restricted to the 52,590 children in care for at least one day in both 2016/17 and 2017/18.

• There are some slight revisions to the previous year’s figures for 2016/17, as a result of revisions to the underlying CLA Census extract produced by DfE. This is common with administrative data and simply reflects updated records in local authorities. This also affects published national statistics: for example the published number of children in care in at the 31st March 2016/17 in the original statistical first release was 72,670; this was revised down slightly to 72,590 in the most recent statistical release. To ensure consistency with published totals, levels of placement instability in 2016/17 have been recalculated based on this revised underlying data. This means results for 2016/17 (and other previous years) presented below may not match those in the 2018 Stability Index publication exactly, though differences are minor.

Data cleaning

As with previous years, details on children’s school histories are sourced via matching the CLA Census to the Pupil Level School Census. This provides information on school entry dates as well as other characteristics contained in these school records - for example any SEN provision or any contact time with a pupil referral unit (PRU). School moves are defined based on these school entry dates. A mid-year school move is defined as a change of school where the start date at the new school occurs after the first 3 weeks of September in the relevant academic year.

Based on feedback on last year’s report, we have made some improvements to the methodology for counting school moves. These amendments mean that figures in this report for previous years will not match those reported in previous Stability Index publications (though differences are for the most part minor), as previous years’ figures have been recalculated to incorporate these amendments. The amendments are:

• We have removed the need for a child to be enrolled at school in both the Autumn and Summer term censuses of a particular academic year. This restriction had been included in previous years to avoid counting school moves due to immigration, but it meant that children out of school at either the Autumn or Summer census dates were excluded the sample, resulting in in a low match rate to the CLA Census. It also excluded a number of children with more unstable school histories, likely resulting in an underestimate of the levels of school instability experienced. We have now replaced this condition with the condition that a child must be in any of the termly school censuses during the relevant time period. This is has resulted in a higher match rate between with the CLA Census.

• We have better accounted for schools that have academised. In some cases, academisation can result in school entry dates being (incorrectly) recorded as the date of the school’s academisation. To counter this, we have mapped schools’ LAESTAB codes to the DfE’s InstitutionID codes (a unique identifier used to link predecessor and successor schools). A child’s school entry date is then defined as the earliest entry date associated with an InstitutionID.

• As with last year, when looking at any school moves (including entry dates in the first three weeks of September), we have excluded moves from primary to secondary school. However, this year we have also been able to better account for moves that were from primary to middle school or middle school to secondary. These moves are now excluded from our measure start of year school moves.

• Previously there has been a slight mismatch between time periods across the three domains, with school moves being defined at any point during the academic year whereas placement and social worker changes are based on financial years. These have been aligned in this year’s report: all school changes are now counted over the year to March.

• This year we have matched the CLA Census to the School Census via both a child’s Unique Pupil Number (UPN) and any former UPNs. This allows us to better account for differences in recording of UPNs between the two datasets. Any duplicates have been excluded based on the DfE’s derived pupil matching reference (PMR), and records have been excluded where multiple dates of birth or gender are associated with a UPN or former UPN.

It should also be noted that matching to the School Census by definition excludes looked after children who have not yet entered or who have left school, as well as many of those in further education institutions not covered by the School Census and those in the independent sector. The analysis will also miss children not currently enrolled in school or those not assigned a UPN at any point.

Matched sample profile

The overall match rate with the School Census for all children in care at the 31st March 2018 was 74% (a considerable improvement over the 56% match rate achieved in last year’s Stability Index). This results in a matched sample size of 54,690. Table 2 below demonstrates the characteristics of this matched sample compared to all LAC aged 5+.

Table 2: Profile of matched CLA and School Census sample

Note: Given the limitations of the School Census dataset it is useful to look at match rates for those aged 5-15. This gives a better indication of non-matching due to data quality rather than coverage of the School Census. The match rate for 5-15 year olds is 95% suggesting the vast majority of those in care that are likely to be covered by the School Census have some form of school history during the 2017/18. This compares to a corresponding match rate of 85% achieved in last year’s analysis.

Data cleaning

As with last year we excluded:

• Duplicated episodes (based on child, local authority and social worker identifiers as well as episode start and end date)
• Episodes without a valid start date
• Children without an open social worker episode on 31 March 2018
• Episodes where multiple primary social workers overlap entirely - for example where a primary social worker may have been on leave for a short period of time and this has been recorded as a change in social worker. In these cases, this analysis includes the episode with the earliest start date
• Children not matched with the CLA Census - children are matched on their unique CLA Census identifier or their Unique Pupil Number. Non-matching identifiers were also checked with their nearest equivalents in the CLA Census to ensure matching failures were not due to simple typos
• Episodes without a meaningful social worker identifier

Matched sample profile

After this cleaning and matching to the CLA census, this gave a final sample size of 69,200 children in care at the 31st March 2018 with information on their social worker histories. Table 3 below demonstrates that the profile of this matched sample is very similar to the profile of the full CLA census population.

Table 3: Profile of matched social worker sample

Placement stability in 2017/18

Overall, rates of multiple placement changes amongst LAC in 2017/18 are similar to those in 2016/17 (Table 4). 10.4% (7,880) of children experienced 2 or more placement changes in 2017/18 compared to 10.6% (7,680) in 2016/17. This shows that there remains a minority of around 1 in 10 children that are experiencing multiple placement moves within a year.

Table 4: Cumulative distribution of number of placement changes during the year

Measures of planned placement changes are limited in the CLA census, particularly with regards to the degree to which the child has been involved in the decision. However, some limited indications are available from the recorded reason for a placement change. This suggests that, of placement changes where a child experiences a change in carer, 39.3% were due to a change in (or in line with) a child’s care plan. The next most common reason is that the placements ended due to the carer’s request (23.3%). In only 4.9% of placement changes did the child request the end of the placement (Note: this is likely an under count as only the main reason for a placement change is recorded, meaning that placements ending by mutual consent are impossible to identify). As a note of caution, it should be borne in mind that in 1 in 4 cases, the reason for the placement change was recorded as ‘Other’. These rates are very similar to the previous year (Table 5).

Table 5: Reasons for placement changes recorded in 2016/17 and 2017/18 CLA Census. Note: base is number of placement changes experienced by the cohort during the year. %s exclude placement changes where no information is recorded

Children whose first placement during the year was an entry into care accounted for 45% of the placement moves during 2017/18. While this is slightly higher than their share of the population in care at the 31st March (40%), this suggests that the majority of placement changes are for children already in care at the start of the year.

Around 1 in 3 of all placement changes during the year (35%) occurred after the placement had lasted for 6 months or longer. This is similar to the level in 2016/17 (36%).

Longer term placement stability

Looking over 2 years suggests that longer term instability is also broadly unchanged between 2016/17 and 2017/18. 2.7% of children in care at the 31st March 2018 in care in both 2016/17 and 2017/18 (1,420 children) had experienced 2+ placement changes in both these years. This compares to 2.6% of those in care at the 31st March 2017. This suggests that (for those in care for both years) 28% of those experiencing 2+ placement moves in 2017/18 had also experienced 2+ placement changes the previous year.

Looking over longer time periods, it remains the case that most looked after children will have experienced a change in placement over the last 3 years (Table 6). These rates are also largely unchanged compared to the cohort of children in care at the 31st March 2016/17.

Table 6: Placement stability over 2-4 years

Average rates of 2+ placement moves over 2016/17 and 2017/18

Given this variation in rates by local authority, it is useful to examine which factors help explain this variation. The correlations below focus on the average rate across 2016/17 and 2017/18 as this helps to account for fluctuations between years in an LA and helps to highlight those that have persistently higher levels.

Figure 3 demonstrates that it is primarily factors relating to the complexity and legal status case mix in an LA which have the strongest correlations with average levels of placement instability over the 2 years.

For example a rate of teenage care entrants 10 percentage points higher than average is associated with a 3 percentage point higher (on average) rate of multiple placement moves. Similarly, a 10 percentage point higher rate of children looked after under section 20 is associated with 0.7 percentage point higher (on average) rate of multiple placement moves.

While the analysis does indicate that there are factors with a statistically significant correlation with placement stability rates, together they explain only 15% of the variation between LAs in rates of placement instability. This suggests there are other unmeasured factors that drive the majority of this variation.

Figure 3: Correlations at LA level between various factors and rates of multiple placement changes in 2017/18

As with last year, there appears to be no correlation between an LA’s Ofsted rating³ for Looked After Children and its rate of multiple placement moves. LAs rated ‘Inadequate’ have the same average rates of children with 2+ placement moves in 2017/18 to those rated ‘Outstanding’ (Table 7).

Table 7: Average rates of multiple placement moves by LA LAC Ofsted rating

There is also notable variation amongst LAs within these Ofsted rating categories (Figure 4). For example, average rates of multiple placement moves over 2016/17 and 2017/18 range from 4% to 23% in local authorities rated Good.

Figure 4: Distribution of rates of multiple placement changes by LAC Ofsted Rating