Abstract
Objectives
The modified Naranjo algorithm assesses the physician assigned cause-effect relationship for homeopathic medicines. It is being adopted in homeopathy researches, but not yet validated systematically. We intended to validate the modified Naranjo algorithm by examining its psychometric properties.
Methods
An online survey sought agreement of 25 experts on the 10 items of the tool on 5-point agreement scale. Next, 285 responses from collected prospectively from chronic cases enrolled under the clinical verification program of the council in 2018 were subjected to testing of construct validity using exploratory principal component analysis (PCA). Confirmatory factor analysis (CFA; n=150) was performed to verify the goodness-of-fit of the model. Reliability was tested using internal consistency, test–retest reliability, and inter-rater reliability by kappa statistics.
Results
Experts’ responses mean values were 4 or higher (i.e. responses were relevant) and standard deviations were less than 1 (i.e. less heterogeneous). In PCA using varimax, all the items loaded above the pre-specified value of 0.4 and identified 4 components explaining 64.1% of variation. The goodness-of -fit of the 4-component CFA model was acceptable (chi-square 89.253, p<0.001). Internal consistency (Cronbach’s alpha 0.7) was borderline; test–retest reliability was acceptable. Kappa statistics was moderate to fair, but poor for few of the items.
Conclusions
Statistical evaluations indicate that the modified Naranjo algorithm is useful, but needs improvement.
Acknowledgement
The authors are grateful to the patients for their sincere participation.
-
Research funding: Central Council for Research in Homoeopathy, Ministry of AYUSH, Govt. of India.
-
Author contributions: RKM, LR, AD, PSC, MK, SS: concept, design, literature search, data extraction, statistical analysis and interpretation, and preparation of the article; PSC, AM, AC, VGP, PS, CK: clinical study and data acquisition. All the authors edited, reviewed, and approved the final article.
-
Competing interest: The funding organization has no role to play in conduct of the study and preparation or publication of the manuscript.
-
Informed consent: Consent was obtained from all individuals included in the study.
-
Ethical approval: Clearance was obtained from the central ethical committee of the Council held on Sept. 7, 2005 for clinical verification prior to initiation of the study.
References
1. Linde, K, Fässler, M, Meissner, K. Placebo interventions, placebo effects and clinical practice. Philos Trans R Soc B Biol Sci 2011;366:1905–12. https://doi.org/10.1098/rstb.2010.0383.Search in Google Scholar PubMed PubMed Central
2. Bikker, AP, Mercer, SW, Reilly, D. A pilot prospective study on the consultation and relational empathy, patient enablement, and health changes over 12 months in patients going to the Glasgow Homoeopathic Hospital. J Alternative Compl Med 2005;11:591–600. https://doi.org/10.1089/acm.2005.11.591.Search in Google Scholar PubMed
3. Reilly, D, Mercer, SW, Bikker, AP, Harrison, T. Outcome related to impact on daily living: preliminary validation of the ORIDL instrument. BMC Health Serv Res 2007;7:139. https://doi.org/10.1186/1472-6963-7-139.Search in Google Scholar PubMed PubMed Central
4. Rutten, ALB, Stolper, CF, Lugten, RFG, Barthels, RWJM. Statistical analysis of six repertory rubrics after prospective assessment applying Bayes’ theorem. Homeopathy 2009;98:26–34. https://doi.org/10.1016/j.homp.2008.11.012.Search in Google Scholar PubMed
5. Naranjo, CA, Busto, U, Sellers, EM, Sandor, P, Ruiz, I, Roberts, EA, et al.. A method for estimating the probability of adverse drug reactions. Clin Pharmacol Ther 1981;80:289–95.10.1038/clpt.1981.154Search in Google Scholar PubMed
6. Rutten, ALB. The importance of case histories for accepting and improving homeopathy. Compl Ther Med 2013;21:565–70. https://doi.org/10.1016/j.ctim.2013.10.001.Search in Google Scholar PubMed
7. Rutten, ALB. Data collection: treat every variable as a treasure. Homeopathy 2015;104:190–6. https://doi.org/10.1016/j.homp.2014.11.002.Search in Google Scholar PubMed
8. van Haselen, RA. Homeopathic clinical case reports: development of a supplement (HOM-CASE) to the CARE clinical case reporting guideline. Compl Ther Med 2016;25:78–85. https://doi.org/10.1016/j.ctim.2015.12.019.Search in Google Scholar PubMed
9. lmhi.org [Internet]. Izmir, Turkey: Liga Medicorum Homoeopathia Internationalis; c2014 [cited 2018 Feb. 10]. Available from: http://www.lmhi.org/downloads/nvp/Project%20LMHI%20WG-%202017.pdf.Search in Google Scholar
10. WissHom. Scientific Society for Homeopathy [Internet]. Hamburg, Germany: cMs. Bettina Atteln [cited 2018 Feb. 10]. Available from: http://www.wisshom.de/dokumente/upload/ae78e_e2dd4_2013_guidelines_clinical_verif_hom_symptoms_third_edition.pdf.Search in Google Scholar
11. Rutten, ALB, Klein-Laansma, CT. Cough and homeopathy mixed methods research. Vienna: ECH conference; 2015 (accessed by ResearchGate).Search in Google Scholar
12. Lamba, CD, Gupta, VK, van Haselen, R, Rutten, L, Mahajan, N, Molla, AM, et al.. Evaluation of the modified Naranjo criteria for assessing causal attribution of clinical outcome to homeopathic intervention as presented in case reports. Homeopathy 2020;109:191–7. https://doi.org/10.1055/s-0040-1701251.Search in Google Scholar PubMed
13. Kent, JT. Lectures on homoeopathic philosophy, Reprinted 4th ed. New Delhi, India: B. Jain Publishers; 1997.Search in Google Scholar
14. Rutten, ALB, Stolper, CF, Lugten, RFG, Barthels, RW. ‘Cure’ as the gold standard for likelihood ratio assessment: theoretical considerations. Homeopathy 2004;93:78–83. https://doi.org/10.1016/j.homp.2004.03.001.Search in Google Scholar PubMed
15. Marx, RG, Menezes, A, Horovitz, L, Jones, EC, Warren, RF. A comparison of two time intervals for test–retest reliability of health status instruments. J Clin Epidemiol 2003;56:730–5. https://doi.org/10.1016/s0895-4356(03)00084-2.Search in Google Scholar
16. Gorsuch, RL. Exploratory factor analysis: its role in item analysis. J Pers Assess 1997;68:532. https://doi.org/10.1207/s15327752jpa6803_5.Search in Google Scholar PubMed
17. Guadagnoli, E, Velicer, WF. Relation of sample size to the stability of component patterns. Psychol Bull 1988;103:265. https://doi.org/10.1037/0033-2909.103.2.265.Search in Google Scholar PubMed
18. Preacher, K, MacCallum, R. Exploratory factor analysis in behavior genetics research: factor recovery with small sample sizes. Behav Genet 2002;32:153. https://doi.org/10.1023/a:1015210025234.10.1023/A:1015210025234Search in Google Scholar
Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/jcim-2020-0434).
© 2021 Walter de Gruyter GmbH, Berlin/Boston
