An essential tool in precision medicine is companion diagnostics, which are medical devices used to assess critical information about the safety and effectiveness of corresponding drugs or biologic products. However, most conventional companion diagnostics are limited by their inability to test multiple genes or assess a broad range of genomic changes that can inform disease identification and care decisions.
This Horizon Scan summarizes the available information regarding the emerging technology of liquid biopsy–based multi-cancer early detection tests for cancer screening. This scan focuses specifically on the Galleri (GRAIL Inc.) and CancerSEEK (Exact Sciences) tests, which are further along in the development cycle and are being assessed in different international clinical studies.
No relevant literature was identified regarding the diagnostic test accuracy, clinical utility, and cost-effectiveness of serum folate testing in people with suspected folate deficiency.
Additionally, no evidence-based guidelines were identified regarding the use of serum folate testing in people with suspected folate deficiency.
Findings from 3 diagnostic accuracy studies indicate that individual tests are insufficient to diagnose vitamin B12 deficiency, and a testing strategy that uses homocysteine and methylmalonic acid should be used in individuals suspected or at risk of vitamin B12 deficiency. This is supported by a health technology assessment that concluded that the current evidence does not provide enough information to determine the most appropriate test, or combination of tests to use in these patients.
The patient populations varied in the primary studies included in the systematic reviews and in the primary studies identified in this review, which may impact the generalizability of the results.
Reference standards and cut-off values (i.e., thresholds) used to diagnose vitamin B12 deficiency varied in the primary studies. Presentation of units (e.g., pg/mL, pmol/L) also varied, making it difficult to compare results across studies.
No studies were identified that evaluated the clinical utility of vitamin B12 testing in people with suspected vitamin B12 deficiency.
No studies were identified that evaluated the cost-effectiveness of vitamin B12 testing in people with suspected vitamin B12 deficiency.
No evidence-based guidelines were identified regarding the use of vitamin B12 testing in people with suspected vitamin B12 deficiency.
An update to a 2020 Canada's Drug Agency Rapid Review was conducted to capture new literature published since 2019 examining the effectiveness of drug treatment informed by genetic testing compared to usual care for adults with depression. Eleven studies were identified: 1 systematic review, 1 health technology assessment, 4 randomized controlled trials reported in 5 publications, 1 non-randomized study, 1 cohort study with historical control, and 2 uncontrolled before-and-after studies. Similar to the conclusions of the 2020 Canada's Drug Agency report, the effectiveness of gene testing for treating depression was unclear. In patients with depression, some studies showed that there were improvements in the clinical effectiveness outcomes in those who received gene testing and other studies showed that there was no difference in outcomes between those who received gene testing and those who did not. No studies showed that gene testing resulted in worse outcomes compared to those who did not receive gene testing. In the current report, the were several limitations across studies such as poor design, inclusion of subjectively measured outcomes, small sample sizes, and a focus on hospital settings all of which may not be generalizable to other populations.
This Horizon Scan summarizes the available information regarding the use of self-sampling devices for HPV testing as part of cervical cancer screening programs.
HPV testing for primary cervical cancer screening is not currently a part of any Canadian screening programs. However, several provinces are in the process of implementation and some pilot testing.
Self-sampling is generally as accurate as clinician-collected sampling for HPV testing.
Self-sampling devices for HPV testing could likely be used to increase participation in cervical cancer screening programs.
There is a lack of evidence on the clinical utility of the interferon gamma release assay for identifying latent tuberculosis infection in rural and remote settings. In remote Indigenous communities with known history of bacillus Calmette-Guérin vaccination, more positive tests results were reported with the tuberculin skin test than with the interferon gamma release assay.
The evidence regarding the cost-effectiveness of the Xpert Mycobacterium tuberculosis complex and resistance to rifampicin (Xpert MTB/RIF) test compared with smear microscopy in diagnosing tuberculosis is summarized in this report. Results from the included 6 studies showed that Xpert MTB/RIF testing is a cost-effective option compared with sputum smear microscopy. However, the generalizability of the results to the Canadian setting are unclear because of the clinical data source populations, willingness-to-pay thresholds, and assumptions used in the analyses. There is a lack of evidence regarding the cost-effectiveness of Xpert MTB/RIF testing compared with mycobacterial cultures or culture-based susceptibility testing.
A total of six systematic reviews were identified. Three systematic reviews reported on the diagnostic accuracy of Xpert with respect to smear microscopy status. There was variability in the estimates of sensitivities and specificities in both the smear positive and smear negative subgroups in the individual studies included in these three systematic reviews, One systematic review reported that the sensitivity with Xpert was 36% to 44% higher than the sensitivity with smear microscopy. Five systematic reviews reported on the diagnostic accuracy of Xpert and/or Xpert Ultra compared with mycobacterial culture test. The sensitivities of Xpert ranged between 62% and 85%; and the specificities ranged between 98% and 99% (based on four systematic reviews). The sensitivities of Xpert Ultra ranged between 64% and 100%; and specificities ranged between 96% and 100% (based on two systematic reviews). Six systematic reviews reported on the diagnostic accuracy of Xpert or both Xpert and Xpert Ultra for the detection of rifampicin resistance compared to culture-based drug susceptibility testing. For rifampicin resistance detection with Xpert, the sensitivities ranged between 83% and 100%, and the specificities ranged between 97% and 100% (based on six systematic reviews). For rifampicin resistance detection with Xpert Ultra the sensitivities ranged between 93% and 95%, and the specificities ranged between 98% and 99% (based on two systematic reviews. The findings need to be interpreted in the light of limitations (such as variations in specimen types and settings; limited evidence for Xpert Ultra; and lack of generalizability with respect to the Canadian setting).
Building inclusive health care services with Indigenous peoples is not the exclusive domain of settler service providers, but requires ongoing participation of, direction and oversight from Indigenous peoples living in the locations where services will be or are currently located.Building inclusive health care services begins at the stage of identifying exclusion through the examination of assumptions and norms across all levels of service provision (e.g., individual, interpersonal, institutional, systemic) This process involves ongoing critical reflection on the part of leaders and practitioners of the ways in which individual behaviors and institutional or systemic attributes may reinforce and perform exclusion.Building inclusive health care services requires ongoing development and uptake of practices directed at addressing the specificity of these exclusions in health care service provision. Building inclusive health care services requires ongoing consideration of the external factors relevant to the specific service area and exploration of opportunities to reframe inclusion from how can we bring or include Indigenous peoples into our care services to how can we participate and include our practice into the lived realities of the communities we are situated within.