Ethnic and racialised inequalities in cancer services: evidence review

2. Methodology

2.1 Research Advisory Group

A Research Advisory Group (RAG, see Appendix A: Acknowledgements) was established to support and advise this review. Membership included external academics, a PHS consultant, Cancer Research UK (CRUK) and SG policy officials and researchers. Some members have specific expertise in anti-racism.

2.2 Search Strategy

Inclusion criteria for the review are set out in detail in Appendix B. The search timeframe was 2010-2025, which was considered proportionate to identify sufficient timely and relevant evidence. The search terms used drew on those used for the RHO Rapid Evidence Review and added terms relevant to cancer.

An initial search was undertaken using KandE, the SG online search engine which provides access to a range of databases. That search prioritised primary research undertaken in Scotland and evidence reviews undertaken in the UK, Ireland and Scandinavian country members of the International Cancer Benchmarking Partnership (ICBP). (The other ICBP members covering parts or all of Canada, the USA, Australia and New Zealand were excluded as it was considered that their ethnicity contexts were less relevant to the Scottish context compared with the other European countries included). However, it was evident that the studies identified by this initial search were too narrow in scope and would present an incomplete picture of evidence relevant to the research questions along the cancer pathway. The search was therefore widened to cover additional databases (see Appendix B) and to include primary research from the rest of the UK. Evidence identified by CRUK in relation to cancer treatment was also reviewed. Citations in a scoping review of data sources used to measure cancer inequalities in the UK were also checked^[9]. Literature was identified and reviewed during the period January – June 2025.

An initial pre-screening process was undertaken to review the abstracts of literature identified, in order to identify and focus on publications which would address notable gaps in the findings from the initial search, covering early diagnosis, treatment and/or barriers to and enablers of uptake of services. Due to the limited availability of evidence from Scotland, most of the evidence reviewed was from England. Some reviews cited evidence from beyond the review’s initial geographic scope: discussion of this evidence has been kept to a minimum to maximise relevance to Scotland.

Cancer-related evidence cited in this review is summarised as follows. The majority of this evidence was subject to a peer-review process, which enhances the quality of the final publication.

Other wider contextual evidence has also been cited. This includes grey literature identified through suggestions from RAG members and snowballing (identifying new citations from the references of literature already reviewed) to contextualise the review findings appropriately. Voluntary Health Scotland, the national intermediary and network for voluntary health organisations in Scotland, issued a call for evidence in their members’ newsletter: some evidence was submitted, some of which is reflected in this review.

2.3 Analysis and Critical Appraisal

Qualitative data identified was analysed thematically. This involved reading of and familiarisation with the data, assigning initial codes to identify specific features within the data, and developing themes to organise the codes into meaningful groups which show patterns within the data.

For primary research studies, to support a proportionate approach to assessing the quality of evidence, the Mixed Methods Appraisal Tool (MMAT) ^[10] was used for quality appraisal. Most studies included were categorised as qualitative studies or quantitative descriptive studies, with a small number of mixed methods studies. Each category of study had its own quality criteria, with the key criterion for each relating to the appropriateness of the method or its application to answer the study research questions. Most studies did not specify their research questions but instead set out study aims and/or objectives. The quality of the evidence reviewed was relatively high overall and informative in relation to the study aims or objectives. All studies met the quality threshold for inclusion.

The tool Critically Appraising for Antiracism ^[11] was reviewed but was not used in full because of capacity constraints. It informed a basic assessment of whether the 77 cancer-related publications cited discussed the impact of structural, systematic / systemic or institutional racism. Nine of those publications did this explicitly; a further 16 alluded to these issues. Relevant evidence is discussed in Section 4.3.

2.4 Limitations

Some aspects of this review were constrained by time and capacity, with the searches and review of the evidence identified undertaken by a single researcher. This informed a pragmatic approach to searching and reviewing to target specific evidence gaps and priority areas of interest that would be informative and relevant for Scotland’s next Cancer Action Plan. A rapid evidence review approach was adopted to synthesise the literature, summarise and analyse it narratively. As a result, this analysis is not based on a comprehensive systematic review of the evidence base, and the literature included is not exhaustive.

The Mixed Methods Appraisal Tool (MMAT) was used as a resource-efficient method to assess evidence from different types of studies (qualitative, quantitative and mixed methods studies). This quality appraisal tool is less detailed than those used for full systematic reviews. However, the MMAT has been validated for usability and content validity^[12],[13].

The Critically Appraising for Antiracism tool was used to inform a basic assessment of whether racism was discussed. This meant that appraisal was less detailed than a comprehensive application of the tool would have provided. Applying the tool in this way was considered appropriate and proportionate for this review.