The objective of this review was to determine efficacy of rehabilitation interventions on work outcomes and identify core content and suitable measurement tools for interventions for women with breast cancer. The findings highlight variability across interventions for women with breast cancer, in intervention effectiveness, content, and delivery, currently available in published literature. Therefore, it is challenging to offer definitive recommendations on what constitutes an effective intervention to support work outcomes for women with breast cancer.
Only one study observed statistically significant differences in work outcomes between intervention, and control groups, observing greater resumption of work and participation in overall work activities at 12-months [28]. The success of this study could be partially explained by its multidisciplinary format providing exercise, psychological and dietary advice or to the sample size which may have been more adequately powered than other studies. A recent Cochrane review identified moderate quality evidence for multidisciplinary interventions in enhancing RTW rates across all cancer types [11]. Despite this, some aspects of the intervention (e.g., thermal water treatment) may be impractical if applied to informing a work-focused intervention, where thermal water treatment facilities are not widely available in healthcare services. In addition, no work-related content was included in the intervention. Lack of statistically significant impact on work outcomes across the other studies can perhaps be explained by the fact that the majority of interventions did not specifically focus on work in their interventions. Evidence suggests that interventions which are designed to target management of a specific concern, result in significant effects on that specified outcome [29]. While three studies in this current review included work components in their intervention, the content varied, and no statistically significant results were observed for work outcomes [17, 22, 23]. This could be because there was insufficient work-specific content in the interventions. Another explanation could be that the studies comprised of small sample sizes. For example, despite Hubbard et al including work-specific content in their intervention, only 18 women participated [17]. Future RCTs with larger samples may provide further insight into effectiveness using work-directed approaches. While work outcomes were measured across all studies by self-report, they varied from quantifying number of working days/hours to whether the participant had returned to work (yes/no response). Measuring RTW by binary yes/no could be problematic where the definition of RTW is blurred. As Lamore et al highlighted, RTW does not necessarily indicate that a previous lifestyle is completely restored, and there needs to be clarity as to the definition of RTW [30]. Researchers could consider if work outcomes imply RTW full-time or part-time, and perhaps perceived satisfaction with the outcome.
It is well documented that treatment and disease-related symptoms such as cancer-related fatigue, cognitive changes, and anxiety can impact on work ability and could be targeted as part of a RTW intervention [9, 10]. Therefore, physical, psychological and QoL outcomes were also examined in this review. Outcomes differed widely across studies, with varying results making it challenging to offer definitive recommendations for the content and delivery of interventions to support return to work. Of the four studies measuring fatigue, significant improvements were observed only in a physical intervention [25]. Interventions which deliver aerobic exercise have previously been cited in a Cochrane Review as beneficial in reducing cancer-related fatigue [31]. Another Cochrane Review reported limited evidence for psychosocial interventions in reducing fatigue unless specifically targeting fatigue [32]. An update of evidence is warranted however as the review was conducted more than a decade ago. In contrast, of the four studies measuring the impact of interventions on QoL, three which reported improvements, delivered both physical and psychosocial interventions. This underlines the importance of a multidisciplinary approach in RTW interventions in targeting a holistic range of treatment- and disease-related factors that impact on work. Interventions targeting QoL have varied considerably in participants, delivery and content making it difficult to arrive at a firm conclusion regarding effectiveness, although a Cochrane review tentatively concluded potential benefit of interventions which are educational and offer supportive attention [33]. Some specific outcomes of interest that are known to impact on work, were under-reported. For example, financial status, social support and cognitive dysfunction were less commonly reported outcomes, but could be considered, particularly as they can impact on RTW [8, 34]. In addition, considering upper limb function could be important for women with breast cancer, who are more likely to experience upper limb impairment compared to other cancer groups [8]. Lymphoedema, for example, is known to compound RTW challenges where there may be restrictions in mobility or heavy lifting, for example [35].
There also remain few studies reporting intervention cost-effectiveness. This gap is important to note as economic evaluation is a key consideration for decision-makers and is also outlined as a pillar for evaluation of complex interventions under the Medical Research Council framework for complex interventions [19]. Two of the nine studies reporting cost-effectiveness, observed contrasting results. One study observed higher costs for the intervention group who typically sought greater use of healthcare services than the control group [22]. This could be because women in the intervention received education on availability of healthcare professionals to assist with symptom management. Greater self-awareness of one’s own health status could lead to a willingness to self-manage health and seek out appropriate health services. This could lead to reduced or self-managed co-morbidity in the future which could provide a cost-benefit for the intervention. In contrast, Mourgues et al observed enhanced work outcomes, and reported the intervention was cost-effective at 12 months [28]. It is not clear however if, like Björneklett et al, consultations with healthcare professionals other than medical professionals were also included in the analysis [22]. Mourgues et al did however use two facilitators as part of their intervention, whereas Björneklett et al use seven from a variety of disciplines [22, 28]. This is likely to have impacted on the overall costs of each intervention. While multidisciplinary interventions have been identified as impacting on RTW rates in cancer care [11], researchers should take into consideration the overall cost impact if including a large range of disciplines. Future study designs could factor in healthcare utilisation into CEA both in the short- and long-term and avoid small sample sizes which are considered a limitation for calculating CEA.
On reviewing health behaviour change theory underlying study interventions, no clear conclusions on a preferred or most effective model can be drawn. Of the nine studies, only three reported using a theoretical framework, all of which varied. This gap has been previously echoed for other rehabilitation interventions for those with cancer [8, 30, 36] and is noteworthy as incorporating insights from theory is recommended as a key consideration when developing complex interventions [19]. In this current review, none of the theories reported in the three studies were specific to work rehabilitation. For example, Social Cognitive Theory [37] which is often used in behaviour change interventions, was reported in one study [21]. This theory holds promise for understanding RTW motivations, expectations of efficacy, and predicting one’s ability to achieve desired outcomes (i.e., work outcomes), but can be vague in operationalisation [38]. Similarly, while the Biopsychosocial model reported by Hubbard et al is holistic in nature considering biological, psychological and social factors, its generic nature can limit its direct application to work rehabilitation research and practice [17, 38, 39]. With this in mind, the evidence base beyond this current review can be explored for more specific models to occupational rehabilitation. A Cancer and Work Model was developed by Feuerstein et al, for all cancer cohorts, it includes factors that can be addressed by healthcare professionals, individuals living with or beyond cancer, and employers, and could be considered in intervention development [40].
This review provides an update on previous literature exploring return to work interventions for women with breast cancer where only one of four studies included in that review was controlled [15]. In contrast, all nine studies in this review were RCTs, potentially reducing selection bias. This is a promising indication that more rigorous methods are being employed in intervention evaluation. Most studies (n = 6) in this current review were published since 2010 indicating growing research in recent years. Furthermore, a number of protocols for upcoming RCTs testing work interventions for women with breast cancer have been published [41–43], and it is likely that there will be an increased evidence-base to further explore feasibility and effectiveness in the future. There are however limitations in intervention development, where there is a lack of pilot and feasibility studies, which are advocated by several models for guiding intervention development [19, 44]. Three of the nine studies in this current review were pilots, and the six remaining RCT studies did not report a pilot study prior to the full trial. While recruitment, adherence and attendance rates were referred to briefly in four studies [22, 24–26], feasibility was only explicitly reported in two [17, 21]. Lack of piloting and feasibility research can lead to methodological challenges. For example, Jong et al [27] did not report any pilots or feasibility testing of their intervention and experienced recruitment issues during the RCT. Despite adding an additional recruitment site, recruitment remained challenging.
Strengths and limitations
This review offers a collective insight into current evidence available on interventions for women with breast cancer that impact on work outcomes. A systematic search process was applied, limiting bias, and meta-analysis was possible for a number of outcomes which offers a statistical measure of the impact of intervention. Backwards and forwards chaining was completed on relevant texts to ensure complete inclusion of studies. Limitations were also identified. For practical reasons, a limit was applied to eligibility criteria for English-text only. However, this may have restricted other potential texts from being included in the final review. Meta-analysis was completed where possible, however, it is acknowledged that results need to be taken with caution as only two studies could be pooled for each analysis and the interventions examined might have been too heterogenous. There are numerous arguments for and against the meta-analysis of a small number of studies. Valentine and colleagues (2010) [45] argue, however, that given the need for a conclusion, two studies can be used for meta-analysis as all other synthesis techniques are less transparent. The study sizes were also small in several of the included studies, which may have limited the reliability and strength of evidence (power) to support the effectiveness of the interventions being evaluated.
Recommendations for future practice and research
In the absence of a sufficient evidence-base and the ability to make definitive recommendations, clinicians could consider multidisciplinary interventions to support women with breast cancer to return to work, as advocated by de Boer et al [11]. While rehabilitation interventions including work components did not observe statistically significant results, the value of work components cannot be ruled out, particularly where the only study to use a work-directed approach (e.g., work accommodations and modifications) was underpowered. Further research in developing and evaluating RTW interventions for women with breast cancer is warranted. Despite enhanced rigour in the study-designs over the past decade, there remains a paucity in piloting and testing feasibility of work-specific interventions. Future research could incorporate a model of intervention development into the study-design. Patient-reported work outcomes have typically been reported in studies. Objective measures (exploring work performance, for example) could also be considered in future designs. Furthermore, sufficient sample sizes to ensure an adequately powered study are necessary.