Systematic Reviews and Meta-Analyses

Author Year Country Research Design Total Sample Size AMSTAR Score

Methods Outcome

Trenaman et al. 2014; Canada
Systematic Review
AMSTAR= 8
N=14

Population: 14 studies were included in the review that investigated interventions among people with SCI and where employment was an outcome.
Methods: An electronic search of Medline/PubMed, EMBASE, Cochrane database, CINAHL, PsycINFO, Social Science Abstracts and Social Work Abstract databases was performed on 31 December 2013. Exclusion criteria include (i) reviews, (ii) studies not published in English and (iii) non-peer reviewed publications.
Outcome measures: employment status, workplace support, rate of return to work, labour market outcomes, time to productive activities, time to employment
  1. 14 studies met the inclusion criteria: 2 RCTs and 12 observational studies
  2. The strongest evidence finds that supported employment can improve employment outcomes among individuals with SCI.
  3. The use of service dogs has also been shown to improve employment outcomes.
  4. The remaining 12 studies are observational and predominantly focus on vocational rehabilitation programs.
  5. There is a lack of high-quality intervention research that targets employment outcomes in individuals with SCI.

Trenaman et al. 2015; Canada/Switzerland
Systematic Review
AMSTAR=8
N=39

Population: 39 studies were included that investigated factors associated with employment outcomes following SCI.
Methods: Studies published from 1952-2014 were identified through an electronic search of MEDLINE/PubMed, EMBASE, CINAHL, PsycINFO, Social Science Abstracts and Social Work databases.
Exclusion criteria included: (1) reviews (2) studies not published in English (3) studies not controlling for potential confounders through a regression analysis, or (4) studies not providing an effect measure in the form of OR, RR, or HR. Data were categorized based on the International Classification of Functioning, Disability and Health framework, with each domain sub-categorized by modifiability.
Outcome measures: employment, domains: body structures & function, activity & participation, environmental facilitators, barriers, personal factors
  1. 39 studies met the inclusion criteria.
  2. 20 modifiable and 12 non-modifiable factors have been investigated in the context of employment following SCI.
  3. Education, vocational rehabilitation, functional independence, social support, and financial disincentives were modifiable factors that have been consistently and independently associated with employment outcomes.
  4. Future research should focus on determining which factors have the greatest effect on employment outcomes, in addition to developing and evaluating interventions targeted at these factors

Roels et al. 2016; Netherlands
Systematic Review
AMSTAR= 10
N=15

Population: 15 studies were included that studied interventions enhancing employment in people with SCI and reported on effects of interventions on employment rate and duration. Three studies were RCTs. One RCT was of high quality. One RCT was of moderate quality and one was of low quality according to the Grade approach of assessing the quality of evidence.
1 RCT including 201 patients; average years post injury = 12.4y
Methods: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, PsycINFO and SPORTDISCUS databases were searched. Randomized controlled trials (RCTs) and non-randomized studies (NRSs) describing a hospital- or a community-based intervention aiming at employment in a SCI population were selected.
Outcome Measures: Employment rate and duration were primary outcomes. Quality appraisal was done using the SIGN methodology, and the quality of evidence was graded using the Grade approach.
  1. The majority of the studies, 11 out of 15 (73%), were case reports or case series.
  2. Only 1 RCT was of high quality (Ottomanelli et al. 2012), including 201 patients describing an intervention over 1 and 2 years. In this study, the employment rate was 26% after 1 year and 31% after 2 years for competitive work, compared with 10% in the treatment as usual-intervention site (TAU-IS) control group and 2% in the treatment as usual observational site (TAU-OS) after 1 and 2 years.
  3. This RCT showed evidence that a vocational rehabilitation programme based on the principles of supported employment integrated in a multidisciplinary team enhances employment for SCI people.
  4. Other studies were of low quality and describe higher employment rates from 36 to 100%.

Kent & Dorstyn, 2014; Australia
Meta-Analysis
AMSTAR = 10
N = 14

Population: 9,868 participants with SCI; average age = 38.0 ± 9.4yo; time since injury = 11.7 ± 6.6y
Methods: A meta-analysis was conducted to examine and quantify differences in psychological functioning and employment status among adults with an acquired SCI. Fourteen observational studies (N=9,868 participants) were identified from an electronic database search. Standardized mean difference scores between employed and unemployed groups were calculated using Cohen’s d effect sizes. Additionally, 95% confidence intervals, fail-safe Ns, percentage overlap scores and heterogeneity statistics were used to determine the significance of d.
Outcome measures: Cohen’s d effect sizes tests for psychological measures (feelings, QoL, life satisfaction, thoughts & beliefs)
  1. Moderate to large and positive weighted effects were noted across three broad psychological constructs (that could be considered clinically important to employment): affective experience or feelings (dw=3.16), quality of life (dw=1.06) and life satisfaction (dw=0.70). (d=0.2, 0.5 and 0.8 equates to small, medium and large effects, respectively).
  2. The psychological domain of life satisfaction had positive effect sizes with employment ranging from 0.37 to 0.85 (a statistically homogeneous finding).
  3. Higher effect sizes were associated with studies that comprised a greater proportion of males (r=0.56, P=0.04); this finding should be interpreted with caution due to the likelihood of a Type I error (false-positive association) due to the relatively small number of mean effect sizes (n=14) contributing to this finding.

Discussion

We found three systematic reviews and one meta-analysis looking at employment after SCI. The first of two systematic reviews performed by Trenaman et al. (2014) looked at employment outcomes for people after SCI. The strongest evidence finds that supported employment (Ottomanelli et al. 2012, 2013, 2015) and the use of service dogs (Allen & Blascovich 1996) can improve employment outcomes among people with SCI. The majority of research found in the reviews was observational and predominantly focused on vocational rehabilitation programs. Conclusions drawn from vocational rehabilitation programs may be confounded, as individuals could be self-selecting for these programs (Trenaman et al. 2014). Trenaman et al. (2014) recommend that future studies should aim to identify which components of vocational programs in particular have the greatest influence on employment outcomes.

A systematic review conducted by the same authors (Trenaman et al. 2015) found 20 modifiable and 12 non-modifiable factors that had been investigated in the context of employment following SCI. Education, vocational rehabilitation, functional independence, social support, and financial disincentives were modifiable factors that have been consistently and independently associated with employment outcomes. Researchers recommend that future research should focus on determining which factors have the greatest effect on employment outcomes, so that better intervention research with controls could be conducted (Trenaman et al. 2015).

*Modifiable and non-modifiable factors for employment after SCI are described in more detail in Tables 2 and 3.

Kent and Dorstyn (2014) conducted a meta-analysis to determine if any psychological constructs have effects on employment after SCI. They found moderate to large positive effects across three broad psychological constructs (that could be considered clinically important to employment): affective experience or feelings (weighted effect size – dw=3.16), quality of life (dw=1.06) and life satisfaction (dw=0.70) (Generally, d=0.2, 0.5 and 0.8 are considered to be small, medium and large effects, respectively).

Conclusion

There is level 1 evidence (Trenaman et al. 2014) suggesting that supported employment shows the strongest evidence that it can improve employment outcomes amongst individuals with SCI. Service dogs have also been shown to increase employment.

There is level 1 evidence (Kent & Dorstyn et al. 2014) that 3 psychological constructs: affective experiences, quality of life, and life satisfaction could be considered clinically important in their effects on employment.