Quality Assessment of Cohort Studies in Complementary and Alternative Medicine: A Scoping Review Over Two Decades
Abstract
Background: We aimed to investigate the subject matters and the quality of publications detailing the findings of cohort studies within the realm of complementary and alternative medicine (CAM).
Methods: A scoping review was conducted on cohort studies in the CAM field up to the conclusion of 2023. The evaluation of their quality was carried out utilizing the 'Strengthening the Reporting of Observational Studies in Epidemiology' (STROBE) checklist. Moreover, an analysis of their research settings and associated variables, including publication year, type of disease, intervention method, and study field, was conducted.
Results: Overall, 215 articles were identified. The majority of these cohorts, approximately 42.3%, originated from Taiwan, with stroke and cardiovascular diseases emerging as the most prevalent outcomes of interest. The mean STROBE score was 1.38 (SD=0.57) out of 2. The lowest scores were associated with the methods and funding sections. Methodologically, the principal weaknesses were linked to sample size, loss to follow-up, and bias control.
Conclusion: The frequency of cohort studies in CAM was limited, predominantly concentrated in a few countries. Chinese medicine and acupuncture were the main intervention methods, while other CAM interventions received less focus. Furthermore, the quality of these studies was deemed unsatisfactory in most cases.
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10. Chang C-J, Yang Y-H, Chen P-C, et al (2019). Stomach cancer and exposure to talc powder without asbestos via Chinese herbal medicine: a population-based cohort study. Int J Environ Res Public Health, 16(5):717.
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14. Yordanov Y, Dechartres A, Atal I, et al (2018). Avoidable waste of research related to outcome planning and reporting in clinical trials. BMC Med, 16(1):87.
15. Vandenbroucke JP, von Elm E, Altman DG, et al (2007). Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration. Ann Intern Med, 147(8):W163-94.
16. Sharp MK, Utrobičić A, Gómez G, et al (2017). The STROBE extensions: protocol for a qualitative assessment of content and a survey of endorsement. BMJ Open, 7(10):e019043.
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18. Peters MDJ, Marnie C, Colquhoun H, et al (2021). Scoping reviews: reinforcing and advancing the methodology and application. Syst Rev, 10(1):263.
19. Munn Z, Peters MDJ, Stern C, et al (2018). Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Med Res Methodol, 18(1):143.
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25. Jiang Y, Zheng RX, Yu ZY, et al (2022). Traditional Chinese Medicine for HIV-Associated Acute Herpes Zoster: A Systematic Review and Meta-Analysis of Randomized Trials. Evid Based Complement Alternat Med, 2022:8674648.
26. Behzadmehr R, Dastyar N, Moghadam MP, et al (2020). Effect of complementary and alternative medicine interventions on cancer related pain among breast cancer patients: A systematic review. Complement Ther Med, 49:102318.
27. Rajahthurai SD, Farrukh MJ, Makmor-Bakry M, et al (2022). Use of complementary and alternative medicine and adherence to medication therapy among stroke patients: a meta-analysis and systematic review. Front Pharmacol, 13:870641.
28. Shaito A, Thuan DTB, Phu HT, et al (2020). Herbal Medicine for Cardiovascular Diseases: Efficacy, Mechanisms, and Safety. Front Pharmacol, 11:422.
29. Lai Y-T, Lin C-H, Hsieh CC, et al (2022). Combining yoga exercise with rehabilitation improves balance and depression in patients with chronic stroke: A controlled trial. App Sci, 12(2):922.
30. Mortada EM (2024). Evidence-Based Complementary and Alternative Medicine in Current Medical Practice. Cureus, 16(1):e52041.
31. Duan Y, Xu Z, Lin Y, et al (2021). A Scoping Review of Cross-Sectional Studies on Traditional Chinese Medicine. Am J Chin Med, 49(6):1275-96.
32. Zhang Y, Zhang Y, Liu S, et al (2023). Acupuncture for cancer pain: a scoping review of systematic reviews and meta-analyses. Front Oncol, 13:1169458.
33. Tangkiatkumjai M, Boardman H, Walker DM (2020). Potential factors that influence usage of complementary and alternative medicine worldwide: a systematic review. BMC Complement Med Ther, 20(1):363.
34. Jasamai M, Islahudin F, Samsuddin NF (2017). Attitudes towards complementary alternative medicine among Malaysian adults. J Appl Pharm Sci, 7(6):190-3.
35. Rubinger L, Ekhtiari S, Gazendam A, et al (2023). Registries: Big data, bigger problems? Injury, 54 Suppl 3:S39-S42.
36. Huang CH, Lin SK, Lin MC, et al (2023). Acupuncture is associated with reduced dementia risk in patients with insomnia: A propensity-score-matched cohort study of real-world data. J Tradit Complement Med, 13(3):297-305.
37. Liao CC, Chien CH, Shih YH, et al (2023). Acupuncture Is Effective at Reducing the Risk of Stroke in Patients with Migraines: A Real-World, Large-Scale Cohort Study with 19-Years of Follow-Up. Int J Environ Res Public Health, 20(3):1690.
38. Huang CY, Wu MY, Huang MC, et al (2023). The association between acupuncture therapy and the risk of reduced pressure ulcers in dementia patients: A retrospective matched cohort study. Integr Med Res, 12(3):100981.
39. Wang W, Wang YH, Yang K, et al (2023). Traditional Chinese medicine use is associated with lower risk of pneumonia in patients with systemic lupus erythematosus: a population-based retrospective cohort study. Front Pharmacol, 14:1185809.
40. Fang Y, Liu J, Xin L, et al (2023). Traditional Chinese Medicine Compound Preparations Are Associated with Low Disease-Related Complication Rates in Patients with Rheumatoid Arthritis: A Retrospective Cohort Study of 11,074 Patients. Biomed Res Int, 2023:1019290.
41. Huang CW, Tran DNH, Li TF, et al (2019). The utilization of complementary and alternative medicine in Taiwan: An internet survey using an adapted version of the international questionnaire (I-CAM-Q). J Chin Med Assoc, 82(8):665-71.
42. Lee EL, Richards N, Harrison J, et al (2022). Prevalence of Use of Traditional, Complementary and Alternative Medicine by the General Population: A Systematic Review of National Studies Published from 2010 to 2019. Drug Saf, 45(7):713-35.
43. James PB, Wardle J, Steel A, et al (2018). Traditional, complementary and alternative medicine use in Sub-Saharan Africa: a systematic review. BMJ Glob Health, 3(5):e000895.
44. Ghebreyesus T A, Kelley E, Qi Z, et al (2019). WHO global report on traditional and complementary medicine 2019. Gene-va, pp.: 40-41
45. Bero L, Chartres N, Diong J, Fabbri A, et al (2018). The risk of bias in observational studies of exposures (ROBINS-E) tool: concerns arising from application to observational studies of exposures. Syst Rev, 7(1):242.
46. Dai S, Zhou X, Xu H, et al (2020). Evaluation of the reporting quality of observational studies in master of public health dissertations in China. BMC Med Res Methodol, 20(1):230.
47. Wiehn E, Ricci C, Alvarez-Perea A, et al (2021). Adherence to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist in articles published in EAACI Journals: A bibliographic study. Allergy, 76(12):3581-8.
48. Norouzi M, Haghdoost AA, Setayesh M (2024). Quality Assessment of Traditional Persian Medicine Observational Studies. Iran J Public Health, 53(7):1469-1481.
49. Shaghaghian S, Astaneh B (2020). Adherence to the strengthening the reporting of observational studies in epidemiology statement in observational studies published in Iranian medical journals. Iran J Public Health, 49(8):1520-29.
50. Rodríguez Del Águila M, González-Ramírez A (2014). Sample size calculation. Allergol Immunopathol (Madr), 42(5):485-92.
51. Nagarajan VB, Bhide S, Kanase HR, et al (2018). Adherence of Observational Studies Published in Indian Journals to STRO BE Statement. J Assoc Physicians India, 66(12):39-42.
52. Bonvini M, Kennedy EH (2022). Sensitivity analysis via the proportion of unmeasured confounding. J Am Stat Assoc, 117(539):1540-50.
53. Hendriksma M, Joosten MH, Peters JP, et al (2017). Evaluation of the Quality of Reporting of Observational Studies in Otorhinolaryngology - Based on the STROBE Statement. PLoS One, 12(1):e0169316.
54. Irani M, Bashtian MH, Khadivzadeh T, et al (2018). Weaknesses in the reporting of cross-sectional studies in accordance with the STROBE report (the case of congenital anomaly among infants in Iran): a review article. Iran J Public Health, 47(12):1796-1804.
2. Capili B, Anastasi JK (2021). Cohort Studies. Am J Nurs, 121(12):45-8.
3. Metelli S, Chaimani A (2020). Challenges in meta-analyses with observational studies. Evid Based Ment Health, 23(2):83-7.
4. Duan Y, Xu Z, Deng J, et al (2020). A scoping review of cohort studies assessing traditional Chinese medicine interventions. BMC Complement Med Ther, 20(1):361.
5. Hosseini A, Jackson A, Bahramnezhad F (2022). Ethical considerations in interventional studies: A systematic review. Acta Med Iran, 60(10):609-14.
6. Saldanha IJ, Adam GP, Bañez LL, et al (2022). Inclusion of nonrandomized studies of interventions in systematic reviews of interventions: updated guidance from the Agency for Health Care Research and Quality Effective Health Care program. J Clin Epidemiol, 152(8):300-306.
7. Tong Z, He W, Yutong F (2019). Bias control of interventional cohort study and the particularity in the field of traditional Chinese medicine. J Tradit Chin Med, 60(11):923-7.
8. Jung H, Won T, Kim G-Y, et al (2023). Efficacy of acupuncture on cardiovascular complications in patients with diabetes mellitus in Korea: A nationwide retrospective cohort. J Integr Med, 21(2):176-83.
9. Chen S-L, Ho C-Y, Lin W-C, et al (2022). The characteristics and mortality of Chinese herbal medicine users among newly diagnosed inoperable huge hepatocellular carcinoma (≥ 10 cm) patients: A retrospective cohort study with exploration of core herbs. Int J Environ Res Public Health, 19(19):12480.
10. Chang C-J, Yang Y-H, Chen P-C, et al (2019). Stomach cancer and exposure to talc powder without asbestos via Chinese herbal medicine: a population-based cohort study. Int J Environ Res Public Health, 16(5):717.
11. Kong Y-C, Kimman M, Subramaniam S, et al (2022). Out-of-pocket payments for complementary medicine following cancer and the effect on financial outcomes in middle-income countries in southeast Asia: a prospective cohort study. Lancet Glob Health, 10(3):e416-e28.
12. Teut M, Walach H, Varanasi R, et al (2020). Recommendations for Designing, Conducting and Reporting Observational Studies in Homeopathy. Homeopathy, 109(3):114-25.
13. Rahmani N, Salehi A, Molavi Vardanjani H, et al (2020). Using STROBE checklist to assess the reporting quality of observational studies affiliated with Shiraz University of Medical Sciences, and its correlates: a scientometric study from Iran. Scientometrics, 122:989-1001.
14. Yordanov Y, Dechartres A, Atal I, et al (2018). Avoidable waste of research related to outcome planning and reporting in clinical trials. BMC Med, 16(1):87.
15. Vandenbroucke JP, von Elm E, Altman DG, et al (2007). Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration. Ann Intern Med, 147(8):W163-94.
16. Sharp MK, Utrobičić A, Gómez G, et al (2017). The STROBE extensions: protocol for a qualitative assessment of content and a survey of endorsement. BMJ Open, 7(10):e019043.
17. Sharp MK, Tokalić R, Gómez G, et al (2019). A cross-sectional bibliometric study showed suboptimal journal endorsement rates of STROBE and its extensions. J Clin Epidemiol, 107:42-50.
18. Peters MDJ, Marnie C, Colquhoun H, et al (2021). Scoping reviews: reinforcing and advancing the methodology and application. Syst Rev, 10(1):263.
19. Munn Z, Peters MDJ, Stern C, et al (2018). Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach. BMC Med Res Methodol, 18(1):143.
20. Mak S, Thomas A (2022). An Introduction to Scoping Reviews. J Grad Med Educ, 14(5):561-4.
21. Choi SY, Choi SY (2020). Evaluation of the Quality of Case Reports from the Journal of Korean Medicine Based on the CARE guidelines. J Korean Med, 41(2):122-36.
22. Andrade C (2022). Research Design: Cohort Studies. Indian J Psychol Med, 44(2):189-91.
23. Canizares M, Hogg-Johnson S, Gignac MAM, et al (2017). Changes in the use practitioner-based complementary and alternative medicine over time in Canada: Cohort and period effects. PLoS One, 12(5):e0177307.
24. Yang J, Lim KH, Lim KT, et al (2023). Complementary and alternative medicine for long COVID: a systematic review of randomized controlled trials. Ther Adv Chronic Dis, 14:20406223231204727.
25. Jiang Y, Zheng RX, Yu ZY, et al (2022). Traditional Chinese Medicine for HIV-Associated Acute Herpes Zoster: A Systematic Review and Meta-Analysis of Randomized Trials. Evid Based Complement Alternat Med, 2022:8674648.
26. Behzadmehr R, Dastyar N, Moghadam MP, et al (2020). Effect of complementary and alternative medicine interventions on cancer related pain among breast cancer patients: A systematic review. Complement Ther Med, 49:102318.
27. Rajahthurai SD, Farrukh MJ, Makmor-Bakry M, et al (2022). Use of complementary and alternative medicine and adherence to medication therapy among stroke patients: a meta-analysis and systematic review. Front Pharmacol, 13:870641.
28. Shaito A, Thuan DTB, Phu HT, et al (2020). Herbal Medicine for Cardiovascular Diseases: Efficacy, Mechanisms, and Safety. Front Pharmacol, 11:422.
29. Lai Y-T, Lin C-H, Hsieh CC, et al (2022). Combining yoga exercise with rehabilitation improves balance and depression in patients with chronic stroke: A controlled trial. App Sci, 12(2):922.
30. Mortada EM (2024). Evidence-Based Complementary and Alternative Medicine in Current Medical Practice. Cureus, 16(1):e52041.
31. Duan Y, Xu Z, Lin Y, et al (2021). A Scoping Review of Cross-Sectional Studies on Traditional Chinese Medicine. Am J Chin Med, 49(6):1275-96.
32. Zhang Y, Zhang Y, Liu S, et al (2023). Acupuncture for cancer pain: a scoping review of systematic reviews and meta-analyses. Front Oncol, 13:1169458.
33. Tangkiatkumjai M, Boardman H, Walker DM (2020). Potential factors that influence usage of complementary and alternative medicine worldwide: a systematic review. BMC Complement Med Ther, 20(1):363.
34. Jasamai M, Islahudin F, Samsuddin NF (2017). Attitudes towards complementary alternative medicine among Malaysian adults. J Appl Pharm Sci, 7(6):190-3.
35. Rubinger L, Ekhtiari S, Gazendam A, et al (2023). Registries: Big data, bigger problems? Injury, 54 Suppl 3:S39-S42.
36. Huang CH, Lin SK, Lin MC, et al (2023). Acupuncture is associated with reduced dementia risk in patients with insomnia: A propensity-score-matched cohort study of real-world data. J Tradit Complement Med, 13(3):297-305.
37. Liao CC, Chien CH, Shih YH, et al (2023). Acupuncture Is Effective at Reducing the Risk of Stroke in Patients with Migraines: A Real-World, Large-Scale Cohort Study with 19-Years of Follow-Up. Int J Environ Res Public Health, 20(3):1690.
38. Huang CY, Wu MY, Huang MC, et al (2023). The association between acupuncture therapy and the risk of reduced pressure ulcers in dementia patients: A retrospective matched cohort study. Integr Med Res, 12(3):100981.
39. Wang W, Wang YH, Yang K, et al (2023). Traditional Chinese medicine use is associated with lower risk of pneumonia in patients with systemic lupus erythematosus: a population-based retrospective cohort study. Front Pharmacol, 14:1185809.
40. Fang Y, Liu J, Xin L, et al (2023). Traditional Chinese Medicine Compound Preparations Are Associated with Low Disease-Related Complication Rates in Patients with Rheumatoid Arthritis: A Retrospective Cohort Study of 11,074 Patients. Biomed Res Int, 2023:1019290.
41. Huang CW, Tran DNH, Li TF, et al (2019). The utilization of complementary and alternative medicine in Taiwan: An internet survey using an adapted version of the international questionnaire (I-CAM-Q). J Chin Med Assoc, 82(8):665-71.
42. Lee EL, Richards N, Harrison J, et al (2022). Prevalence of Use of Traditional, Complementary and Alternative Medicine by the General Population: A Systematic Review of National Studies Published from 2010 to 2019. Drug Saf, 45(7):713-35.
43. James PB, Wardle J, Steel A, et al (2018). Traditional, complementary and alternative medicine use in Sub-Saharan Africa: a systematic review. BMJ Glob Health, 3(5):e000895.
44. Ghebreyesus T A, Kelley E, Qi Z, et al (2019). WHO global report on traditional and complementary medicine 2019. Gene-va, pp.: 40-41
45. Bero L, Chartres N, Diong J, Fabbri A, et al (2018). The risk of bias in observational studies of exposures (ROBINS-E) tool: concerns arising from application to observational studies of exposures. Syst Rev, 7(1):242.
46. Dai S, Zhou X, Xu H, et al (2020). Evaluation of the reporting quality of observational studies in master of public health dissertations in China. BMC Med Res Methodol, 20(1):230.
47. Wiehn E, Ricci C, Alvarez-Perea A, et al (2021). Adherence to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist in articles published in EAACI Journals: A bibliographic study. Allergy, 76(12):3581-8.
48. Norouzi M, Haghdoost AA, Setayesh M (2024). Quality Assessment of Traditional Persian Medicine Observational Studies. Iran J Public Health, 53(7):1469-1481.
49. Shaghaghian S, Astaneh B (2020). Adherence to the strengthening the reporting of observational studies in epidemiology statement in observational studies published in Iranian medical journals. Iran J Public Health, 49(8):1520-29.
50. Rodríguez Del Águila M, González-Ramírez A (2014). Sample size calculation. Allergol Immunopathol (Madr), 42(5):485-92.
51. Nagarajan VB, Bhide S, Kanase HR, et al (2018). Adherence of Observational Studies Published in Indian Journals to STRO BE Statement. J Assoc Physicians India, 66(12):39-42.
52. Bonvini M, Kennedy EH (2022). Sensitivity analysis via the proportion of unmeasured confounding. J Am Stat Assoc, 117(539):1540-50.
53. Hendriksma M, Joosten MH, Peters JP, et al (2017). Evaluation of the Quality of Reporting of Observational Studies in Otorhinolaryngology - Based on the STROBE Statement. PLoS One, 12(1):e0169316.
54. Irani M, Bashtian MH, Khadivzadeh T, et al (2018). Weaknesses in the reporting of cross-sectional studies in accordance with the STROBE report (the case of congenital anomaly among infants in Iran): a review article. Iran J Public Health, 47(12):1796-1804.
| Files | ||
| Issue | Vol 54 No 1 (2025) | |
| Section | Review Article(s) | |
| Keywords | ||
| Scoping review Quality assessment Cohort studies Complementary therapies | ||
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How to Cite
1.
Norouzi M, Haghdoost AA. Quality Assessment of Cohort Studies in Complementary and Alternative Medicine: A Scoping Review Over Two Decades. Iran J Public Health. 2025;54(1):74-87.
