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Updated: Jun 9, 2022

Abstract Empirical research on how to effectively recruit and retain staff may help organisations to operate more effectively. Such research may also help Animal Advocacy Careers to offer more useful services to the animal advocacy movement. Accordingly, Google Scholar searches were conducted to identify existing reviews and meta-analyses of academic research on recruitment and retention. In total, 52 relevant research items were reviewed and included. Promising actions to improve recruitment outcomes include the use of structured interviews, general mental ability, and conscientiousness to select candidates, improvements to the usability and aesthetics of websites and job ads, and being personable and informative to candidates. Promising actions to improve the retention of staff include the provision of socialisation, education, and support (e.g. mentoring) for new staff and focusing on employee commitment rather than control. Some of the other identified actions seem likely to have positive effects on recruitment and retention but, given the associated costs, may still not be worthwhile; salary increases probably fit into this category.

Introduction Animal Advocacy Careers (AAC) is an organisation that seeks to address the career and talent bottlenecks in the animal advocacy movement, especially the farmed animal movement. The services that AAC could plausibly provide to the movement can be thought of as falling into the following categories:

  1. Improving recruitment and retention,

  2. Upskilling participants in the movement, or

  3. Better coordinating the movement.

AAC has already begun offering a service aimed primarily at recruitment into the movement; our introductory online course and workshop. A clearer understanding of the existing academic research into the effectiveness of various interventions for recruitment and retention could therefore help AAC to improve its services. It could also help AAC prioritise between recruitment and retention or the other categories of possible services. Of course, animal advocacy organisations and other organisations seeking to do good in the world are likely already grappling with questions about how to recruit and retain high-quality staff. A clearer understanding of the existing academic research on recruitment and retention may also help those organisations in their efforts. To address these needs, Animal Advocacy Careers undertook a brief overview of recruitment and retention research. Methodology The research questions were:  1) Which actions can be taken that seem likely to increase the quality of recruited staff to organisations? a) Which actions can be taken that seem likely to improve the outputs and results of hired candidates? b) Which actions can be taken that seem likely to increase the number of applicants? 2) Which actions can be taken that seem likely to increase employee retention? 3) What are the predictors of employee turnover and retention (and what does this imply about which actions can be taken)? Searches of Google Scholar were conducted.[1] The first 5-20 pages of results were skimmed or reviewed for each search term. There were not strict inclusion and exclusion criteria[2] and the likely relevance of research was assessed predominantly by the phrasing of the title.  We focused on existing reviews and meta-analyses rather than on identifying all relevant individual studies, so the interventions identified in the results section below are not exhaustive. The interventions in the results tables below are ordered in terms of effect size. Brief intuitive comments on possible cost-effectiveness are provided. The results section below uses the acronym DEI (diversity, equity, and inclusion). The summaries below are intended to be easily readable and intuitive. If you’d like to dive further into the methodology, see the appendix below. Results 52 research items were reviewed and included in the results spreadsheet. The following caveats about the identified research should be borne in mind:

  • No included meta-analyses or reviews specified that they were limited to randomised controlled trials (RCTs). Where reviews reported on the prevalence of RCTs, they seemed to be rarer than studies using observational design. This means that the strength of evidence is generally weaker than in some other research areas, such as the health behaviour literature.

  • Tests of and adjustments for publication bias were not conducted in relevant reviews and meta-analyses. Again, this should reduce our confidence in the reported effect sizes.

  • More positively, the identified research often used objectively measurable outcomes such as hiring outcomes and turnover behaviour. This should increase our confidence in findings relative to some other research areas, such as research relating to the characteristics of good management and leadership.

1a: Which actions can be taken that seem likely to improve the outputs and results of hired candidates? The reviewed research suggests a number of actions can be taken to improve the outputs and results of hired candidates.

1b: Which actions can be taken that seem likely to increase the number of applicants? The reviewed research suggests a number of actions can be taken to increase the number of applicants. Of course, this is only useful insofar as it improves the outputs and results of hired candidates. However, some research focuses on applicant numbers rather than job performance. All else being equal, having more applicants to choose from should, on average, lead to higher quality hires.

Note also:

  • ​Using job boards to promote opportunities seems likely to be worthwhile.[8]

  • One meta-analysis found that the recruiter’s demographic characteristics have no significant effect on the number of applicants.

  • One review focusing on recruitment into research studies found slightly better evidence for social marketing’s effectiveness at sourcing candidates than for referral recruitment’s effectiveness.

2: Which actions can be taken that seem likely to increase employee retention? The fairly extensive research on the predictors of employee turnover (see the section below) does not seem to have encouraged much research on the effectiveness of particular actions to reduce turnover.[9] Hence, the table in this section should be supplemented by the findings in the section below.

Note also:

  • One study found no significant effect of performance appraisals and merit-based pay on turnover. Another study found no significant effect of flexible scheduling.

  • ​Reviewers offering advice on strategies to reduce turnover (Allen, Bryant, and Vardaman 2010 and Ongori 2007) have suggested that, though some practices may result in improved retention across an organisation, the most effective interventions will likely be targeted towards the specific problems that an organisation faces. This hypothesis is untested but seems intuitively likely.

3: What are the predictors of employee turnover and retention? Several relevant meta-analyses were identified for this question, though one (Rubenstein et al. 2018) was notably more recent and comprehensive than the others.[10] Although Rubenstein et al.’s (2018) focus was on predictors of turnover, rather than interventions to reduce turnover, we can draw inferences about interventions that seem likely to be effective at reducing turnover. It may be possible to reduce turnover by looking out for the following traits, abilities, and characteristics during hiring processes:

  • Loyalty, identification with, and enthusiasm for the organisation and their career path. 

  • High conscientiousness, internal motivation, and emotional stability (though they were insignificant as predictors in the meta-analysis). 

  • Ability to cope with demanding and difficult tasks,

  • Likely fit with the organisation and likely job embeddedness (e.g. “connections to other people and activities” and “what an individual would give up by quitting”), though making job offers based partly on these criteria could plausibly have other negative effects, e.g. relating to DEI.

Though these are not likely to be quick and easy to implement, organisational changes that may reduce turnover include:

  • Encouraging loyalty, identification with, enthusiasm for the organisation and individuals’ chosen career path,

  • Ensuring that roles are satisfying, 

  • Giving staff decision-making influence,

  • Ensuring that the organisation has just and fair practices, 

  • Ensuring that staff are well led and managed,

  • Providing rewards beyond pay, such as benefits, career/growth opportunities, and training time (this may do more to reduce turnover than increasing salaries).

Limitations and suggestions for further research

  • This overview focused on academic research identified via Google Scholar. Summaries of “best practice” advice based on organisational experience and intuition (such as via reviews of nonacademic books and general Google searches) could also be useful, though the strength of evidence would be lower per identified item.

  • Similarly, this overview has focused on reviews that quite explicitly focused on evaluating the outcomes of interventions to improve recruitment and retention (though the predictors of turnover were included by necessity). Other research on recruitment and human resources (e.g. as summarised in the respective Oxford handbooks) could offer some relevant further insights.

  • The focus here was on existing reviews and meta-analyses; individual empirical studies were included or excluded somewhat arbitrarily. A more comprehensive review might identify a number of useful studies that have been omitted both from this report and the cited reviews.

  • Most of the findings here come from the private sector; a quick search did not identify reviews of comparable quality that focused specifically on nonprofits and so further research into this topic was not pursued. However, a review of individual studies that focus specifically on recruitment and retention in nonprofits could be useful.

  • A review of research on recruitment and retention of volunteers could be useful.[11]

  • The identified research looked at organisational perspectives on recruitment and retention. Ultimately, the movement-wide perspective is more important. For example, some of the interventions that were identified as promising in this literature review probably work by denying talented staff to other organisations with similar aims; if you see organisations as similarly cost-effective, then this sort of inter-organisation competition will do little to enhance the overall effectiveness of a social movement. Reviewing the relevant sociological and psychological research literature that more specifically addresses actions to affect mobilisation, recruitment, and retention for social movements could also be helpful, but is likely to be somewhat more qualitative and difficult to provide a concise overview of.

  • This overview was not intended to summarise the research literature on the following topics (despite partial overlap with the research here), any of which could be the subject of a separate review:

    • Practices for improving diversity, equity, and inclusion via hiring (though see here).

    • Predictors of job performance, unless explicitly linked to recruitment strategies (though see here).

    • The overall effects of turnover on organisational outcomes.

    • Interventions that might affect various antecedents of turnover (where turnover is not used as the outcome variable).

Appendix: Results spreadsheet and scoring system If you have a strong interest in this research, we encourage you to read the summaries on the full results spreadsheet. To generate the results tables above, a scoring system was used, which is reflected in the “Scores by intervention, question, and item” and “Summary scores by intervention and question” tabs of the results spreadsheet. Each research item was assigned a “naive score” for each question that it provided evidence for. The scores were given on a possible range from -5 to +5.[12] These rankings are based on our interpretation of the information and evidence provided, rather than the ranking that we believe that the author of a research item would choose. Each research item was also assigned a “strength of evidence” (SoE) multiplier for each question that it provided evidence for. The possible SoE multipliers range from 0 to 1, where 0 means that there is no relevant evidence or arguments and 1 means that there is very strong evidence.[13] This was used to create a “question weighted score,”[14] which can be interpreted roughly as the “naive score” is for individual research items, e.g. 1 means “means very low positive impacts” and 5 means “very high positive impacts.” References The full list of references is available in the second tab of the results spreadsheet. Footnotes [1] The search terms used were:

  • (Recruitment OR recruiting OR “talent acquisition” OR hiring) AND (“meta analysis” OR “systematic review”)

  • (headhunting OR “executive search”) AND (“meta analysis” OR “systematic review”)

  • (retention OR turnover) AND (employee OR staff OR hiring) AND (“meta analysis” OR “systematic review”) AND (strategies OR interventions)

  • (determinants OR predictors OR moderators) AND (retention OR turnover) AND (employee OR staff OR hiring) AND (“meta analysis” OR “systematic review”)

Several variations of these search terms were also used, such as adding “AND (“human resources” OR business OR corporate OR profit)” and removing “AND (“meta analysis” OR “systematic review”).” [2] The following criteria were used to decide which items to include:

  • Are the findings directly applicable or at least fairly comparable to the recruitment strategies that an animal advocacy nonprofit could plausibly use? (After reviewing a few meta-analyses about recruitment into clinical trials, further studies on this topic were not reviewed, since the relevance was low.)

  • Does the research item contain (or summarise) substantial empirical findings? (Here, meta-analyses were prioritised over narrative summaries; whether narrative reviews were included was somewhat arbitrary, relying quite substantially on date of publication, title, and citation count to decide whether to read these reviews.)

  • Is the research item unlikely to have been made predominantly redundant by subsequent research? Relevant factors affecting this criterion include the date of publication and any impressions we have of the thoroughness of the literature on the subtopic that it covers.

  • Is the item published in a peer-reviewed academic journal? 

We did not exclude all items that failed to meet some of the inclusion criteria, if they seemed to perform especially well on others. These inclusion criteria were pre-planned. [3] See here. [4] One approach would be to qualitatively seek to hire clever individuals. More systematically, organisations could use assessments as part of an application process; Le et al. (2007) noted that “GMA is most commonly measured in job  candidates by assessments such as the Wonderlic Personnel Test, the  Wesman Personnel Classification Test, or the Watson-Glaser Critical Thinking Appraisal Form.” An alternative is to use candidates’ GPA scores, which, as Imose and Barber (2015) discuss, are a proxy for general mental ability and conscientiousness. See also 80,000 Hours’ discussion of GMA. [5] This is discussed to some extent in Le et al. (2007) and Imose and Barber (2015). [6] This would probably just mean qualitatively seeking to hire hard-working individuals, e.g. placing a lot of weight on evidence that they have done or achieved lots of things. Administering personality tests in a job interview seems cumbersome. [7] See here. [8] Nikolaou (2014) found that “job seekers still seem to use job boards more extensively” than social media. Since this sort of comparison is not well-suited to meta-analysis, it is likely that there is other evidence available on this question that was not identified by this brief overview. [9] The most recent identified meta-analysis was from 1985 and several more specific reviews reporting to focus on interventions to reduce turnover seemed to base their recommendations primarily on the research on the predictors of turnover. [10] If you have a strong interest in turnover and retention, we recommend you read the full paper, or at least our summary in the results spreadsheet. [11] After examining a single study on volunteer management practices’ impact on retention and a single study on volunteer recruitment, it seemed that recruitment and retention issues relating specifically to volunteers are substantially separate and should not be integrated into this review. [12] -5 means that if this was the only relevant evidence on this issue, we would expect this to have strong negative impacts on recruitment or retention, 0 means that we would expect it to have no impact on recruitment and retention (i.e. useless but not harmful), 1 means very low positive impacts, 2 means quite low positive impacts, 3 means moderate positive impacts, 4 means quite high positive impacts, 5 means very high positive impacts. [13] The multiplier was used roughly as follows:  0 = no relevant evidence or arguments (in practice, 0 will never be used, since a paper would not be included if it provided no relevant evidence or arguments). 0.2 = a plausible theoretical argument, with no supporting empirical evidence. 0.4 = a highly convincing and important theoretical argument, or an argument with some supporting evidence, such as from a single observational study, from multiple studies with weak relevance, or from multiple studies where the findings are somewhat contradictory. 0.6 = a highly convincing and important argument with some supporting evidence or a plausible argument with moderate evidence from multiple studies. 0.8 = a highly convincing and important argument with moderate evidence from multiple studies or a plausible argument with strong evidence from multiple studies. 1 = a highly convincing and important argument with strong evidence from multiple studies. [14] For each item, the naive scores were multiplied by the SoE multiplier, to generate a “weighted score.” This metric is of little interest for individual research items, since, for example, items with a naive score of 1 and a SoE multiplier of 5 would have the same weighted score as items with a naive score of 5 and a SoE multiplier of 1, even though such items have opposite implications for the question. Hence, the relevant columns in the “Findings tables” spreadsheet are hidden. When the sum of the weighted scores is divided by the sum of the SoE multipliers, this creates the “question weighted score.”


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