Rachel Rishma Johanna Kalf

Dr. Rachel Rishma Johanna Kalf


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2014 in Genetics in Medicine
Verified
Journal Article
Open access
PDF file
RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
RMRaluca Mihaescu
Raluca Mihaescu
SKSuman Kundu
Suman Kundu
PKPeter de Knijff
Peter de Knijff
RGRobert C. Green
Robert C. Green
AJA. Cecile J.w. Janssens
A. Cecile J.w. Janssens
The promise of personalized genomics for common complex diseases depends, in part, on the ability to predict genetic risks on the basis of single nucleotide polymorphisms. We examined and compared the methods of three companies (23andMe, deCODEme, and Navigenics) that have offered direct-to-consumer personal genome testing. We simulated genotype data for 100,000 individuals on the basis of published genotype frequencies and predicted disease risks using the methods of the companies. Predictive ability for six diseases was assessed by the AUC. AUC values differed among the diseases and among the companies. The highest values of the AUC were observed for age-related macular degeneration, celiac disease, and Crohn disease. The largest difference among the companies was found for celiac disease: the AUC was 0.73 for 23andMe and 0.82 for deCODEme. Predicted risks differed substantially among the companies as a result of differences in the sets of single nucleotide polymorphisms selected and the average population risks selected by the companies, and in the formulas used for the calculation of risks. Future efforts to design predictive models for the genomics of common complex diseases may benefit from understanding the strengths and limitations of the predictive algorithms designed by these early companies. Genet Med 16 1, 85–91.

22 March 2021 in Pharmacology Research & Perspectives
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Journal Article
Open access
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RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
RVRick Vreman
Rick Vreman
DDDiana M.J. Delnoij
Diana M.J. Delnoij
MBMarcel L. Bouvy
Marcel L. Bouvy
WGWim Goettsch
Wim Goettsch
Standard outcome sets developed by the International Consortium for Health Outcomes Measurement (ICHOM) facilitate value‐based health care in healthcare practice and have gained traction from regulators and Health Technology Assessment (HTA) agencies that regularly assess the value of new medicines. We aimed to assess the extent to which the outcomes used by regulators and HTA agencies are patient‐relevant, by comparing these to ICHOM standard sets. We conducted a cross‐sectional comparative analysis of ICHOM standard sets, and publicly available regulatory and HTA assessment guidelines. We focused on oncology due to many new medicines being developed, which are accompanied by substantial uncertainty regarding the relevance of these treatments for patients. A comparison of regulatory and HTA assessment guidelines, and ICHOM standard sets showed that both ICHOM and regulators stress the importance of disease‐specific outcomes. On the other hand, HTA agencies have a stronger focus on generic outcomes in order to allow comparisons across disease areas. Overall, similar outcomes are relevant for market access, reimbursement, and in ICHOM standard sets. However, some differences are apparent, such as the acceptability of intermediate outcomes. These are recommended in ICHOM standard sets, but regulators are more likely to accept intermediate outcomes than HTA agencies. A greater level of alignment in outcomes accepted may enhance the efficiency of regulatory and HTA processes, and increase timely access to new medicines. ICHOM standard sets may help align these outcomes. However, some differences in outcomes used may remain due to the different purposes of regulatory and HTA decision‐making.

8 June 2018 in JMIR Cancer
Verified
Journal Article
Open access
RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
AMAmr Makady
Amr Makady
RHRenske M.T. Ten Ham
Renske M.T. Ten Ham
KMKim Meijboom
Kim Meijboom
WGWim Goettsch
Wim Goettsch
I1IMI-GetReal Workpackage 1
IMI-GetReal Workpackage 1
Patient-Centered Innovations, Education and Technology for Cancer Care and Cancer Research

25 February 2013 in Pharmacogenomics
Verified
Journal Article
Closed access
RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
RBRachel Bakker
Rachel Bakker
AJA. Cecile J.w. Janssens
A. Cecile J.w. Janssens

7 December 2021 in Journal of Medical Internet Research
Verified
Journal Article
Open access
RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
DDDiana M J Delnoij
Diana M J Delnoij
BRBettina Ryll
Bettina Ryll
MBMarcel L Bouvy
Marcel L Bouvy
WGWim Goettsch
Wim Goettsch
Background: There is a general agreement on the importance of health-related quality of life (HRQoL). This type of information is becoming increasingly important for the value assessment of health technology assessment agencies in evaluating the benefits of new health technologies, including medicines. However, HRQoL data are often limited, and additional sources that provide this type of information may be helpful. Objective: We aim to identify the HRQoL topics important to patients with melanoma based on web-based discussions on public social media forums. Methods: We identified 3 public web-based forums from the United States and the United Kingdom, namely the Melanoma Patient Information Page, the Melanoma International Forum, and MacMillan. Their posts were randomly selected and coded using qualitative methods until saturation was reached. Results: Of the posts assessed, 36.7% (150/409) of posts on Melanoma International Forum, 45.1% (198/439) on MacMillan, and 35.4% (128/362) on Melanoma Patient Information Page focused on HRQoL. The 2 themes most frequently mentioned were mental health and (un)certainty. The themes were constructed based on underlying and more detailed codes. Codes related to fear, worry and anxiety, uncertainty, and unfavorable effects were the most-often discussed ones. Conclusions: Web-based forums are a valuable source for identifying relevant HRQoL aspects in patients with a given disease. These aspects could be cross-referenced with existing tools and they might improve the content validity of patient-reported outcome measures, including HRQoL questionnaires. In addition, web-based forums may provide health technology assessment agencies with a more holistic understanding of the external aspects affecting patient HRQoL. These aspects might support the value assessment of new health technologies and could therefore help inform topic prioritization as well as the scoping phase before any value assessment.

21 December 2021 in International Journal of Technology Assessment in Health Care
Verified
Journal Article
Open access
PDF file
RKRachel Rishma Johanna Kalf
Rachel Rishma Johanna Kalf
MZMarloes Zuidgeest
Marloes Zuidgeest
DDDiana M. J. Delnoij
Diana M. J. Delnoij
MBMarcel L. Bouvy
Marcel L. Bouvy
WGWim Goettsch
Wim Goettsch
Objective: Although health technology assessment (HTA) and healthcare quality improvement are distinct processes, a greater level of alignment in outcome measures used may increase the quality and efficiency of data collection. This study evaluates the agreement in outcome measures used in oncology for healthcare quality improvement and HTAs, and how these align to the International Consortium for Health Outcomes Measurement (ICHOM) standard sets. Methods: We conducted a cross-sectional comparative analysis of ICHOM sets focusing on oncological indications and publicly available measures for healthcare quality and HTA reports published by the National Health Care Institute from the Netherlands and the National Institute for Health and Care Excellence from the United Kingdom. Results: All ICHOM sets and HTAs used overall survival, whereas quality improvement used different survival estimates. Different progression estimates for cancer were used in HTAs, ICHOM sets, and quality improvement. Data on health-related quality of life (HRQoL) was recommended in all ICHOM sets and all HTAs, but selectively for quality improvement. In HTAs, generic HRQoL questionnaires were preferred, whereas, in quality improvement and ICHOM sets, disease-specific questionnaires were recommended. Unfavorable outcomes were included in all HTAs and all ICHOM sets, but not always for quality improvement. Conclusions: Although HTA and quality improvement use outcome measures from the same domains, a greater level of alignment seems possible. ICHOM may provide input on standardized outcome measures to support this alignment. However, residual discrepancies will remain due to the different objectives of HTA and quality improvement.