Challenges and opportunities for using population health data to investigate cancer survivors' quality of life in Australia

Utilisation of endocrine therapy for cancer in Indigenous peoples: a systematic review and meta-analysis

BACKGROUND

Indigenous peoples worldwide experience inequitable cancer outcomes, and it is unclear if this is underpinned by differences in or inadequate use of endocrine treatment (ET), often used in conjunction with other cancer treatments. Previous studies examining ET use in Indigenous peoples have predominately focused on the sub-national level, often resulting in small sample sizes with limited statistical power. This systematic review aimed to collate the findings ofarticles on ET utilisation for Indigenous cancer patients and describe relevant factors that may influence ET use.

METHODS

We conducted a systematic review and meta-analysis of studies reporting ET use for cancer among Indigenous populations worldwide. PubMed, Scopus, CINAHL, Web of Science, and Embase were searched for relevant articles. A random-effect meta-analysis was used to pool proportions of ET use. We also performed a subgroup analysis (such as with sample sizes) and a meta-regression to explore the potential sources of heterogeneity. A socio-ecological model was used to present relevant factors that could impact ET use.

RESULTS

Thirteen articles reported ET utilisation among Indigenous populations, yielding a pooled estimate of 67% (95% CI:54 - 80), which is comparable to that of Indigenous populations 67% (95% CI: 53 - 81). However, among studies with sufficiently sized study sample/cohorts (≥ 500), Indigenous populations had a 14% (62%; 95% CI:43 - 82) lower ET utilisation than non-Indigenous populations (76%; 95% CI: 60 - 92). The ET rate in Indigenous peoples of the USA (e.g., American Indian) and New Zealand (e.g., Māori) was 72% (95% CI:56-88) and 60% (95% CI:49-71), respectively. Compared to non-Indigenous populations, a higher proportion of Indigenous populations were diagnosed with advanced cancer, at younger age, had limited access to health services, lower socio-economic status, and a higher prevalence of comorbidities.

CONCLUSIONS

Indigenous cancer patients have lower ET utilisation than non-Indigenous cancer patients, despite the higher rate of advanced cancer at diagnosis. While reasons for these disparities are unclear, they are likely reflecting, at least to some degree, inequitable access to cancer treatment services. Strengthening the provision of and access to culturally appropriate cancer care and treatment services may enhance ET utilisation in Indigenous population. This study protocol was registered on Prospero (CRD42023403562).

Improving Clinical Registry Data Quality via Linkage With Survival Data From State-Based Population Registries

PURPOSE

Real-world data (RWD) collected on patients treated as part of routine clinical care form the basis of cancer clinical registries. Capturing accurate death data can be challenging, with inaccurate survival data potentially compromising the integrity of registry-based research. Here, we explore the utility of data linkage (DL) to state-based registries to enhance the capture of survival outcomes.

METHODS

We identified consecutive adult patients with brain tumors treated in the state of Victoria from the Brain Tumour Registry Australia: Innovation and Translation (BRAIN) database, who had no recorded date of death and no follow-up within the last 6 months. Full name and date of birth were used to match patients in the BRAIN registry with those in the Victorian Births, Deaths and Marriages (BDM) registry. Overall survival (OS) outcomes were compared pre- and post-DL.

RESULTS

Of the 7,346 clinical registry patients, 5,462 (74%) had no date of death and no follow-up recorded within the last 6 months. Of the 5,462 patients, 1,588 (29%) were matched with a date of death in BDM. Factors associated with an increased number of matches were poor prognosis tumors, older age, and social disadvantage. OS was significantly overestimated pre-DL compared with post-DL for the entire cohort (pre- v post-DL: hazard ratio, 1.43; P < .001; median, 29.9 months v 16.7 months) and for most individual tumor types. This finding was present independent of the tumor prognosis.

CONCLUSION

As revealed by linkage with BDM, a high proportion of patients in a brain cancer clinical registry had missing death data, contributed to by informative censoring, inflating OS calculations. DL to pertinent registries on an ongoing basis should be considered to ensure accurate reporting of survival data and interpretation of RWD outcomes.