Author (Year)	Study Type	Psychological Elements of the CAMs	Population	Outcomes and Limitations
Forer (1949) [115]	Experimental	Personal validation fallacy	College students	Outcomes:
				Demonstrated how people tend to accept vague, general personality descriptions as accurate.
				Limitations:
				Limited sample, potential experimenter bias.
Beyerstein (2001) [124]	Review	Reasoning errors in alternative medicine	General population	Outcomes:
				Identified common logical fallacies in CAM beliefs.
				Limitations:
				Lack of empirical data.
Kaptchuk (2002) [116]	Review	Placebo effect in CAM	General population	Outcomes:
				Discussed potential clinical significance of healing rituals.
				Limitations:
				Lack of original data.
Winslow, Shapiro (2002) [108]	Cross-sectional survey	Physicians’ attitudes towards CAM education	American physicians	Outcomes:
				Physicians want more CAM education to better communicate with patients.
				Limitations:
				Potential response bias.
Klein, Helweg-Larsen (2002) [111]	Meta-analysis	Perceived control and optimistic bias	General population	Outcomes:
				Positive correlation between perceived control and optimistic bias.
				Limitations:
				Heterogeneity in included studies.
				The findings may not be generalizable to the use of CAM.
Honda et al. (2005) [99]	Cross-sectional survey	Personality, coping strategies, and social support in CAM use	American adults	Outcomes:
				Personality traits, coping strategies and social support influence CAM use.
				Limitations:
				Self-reported data, potential recall bias.
Singh et al. (2005) [113]	Qualitative study is based on in-person interviews	Motivation for CAM use	Men with prostate cancer	Outcomes:
				Identified various motivations for CAM use, including hope and empowerment.
				Limitations:
				Small sample size.
				Limited generalizability to musculoskeletal care.
Shih et al. (2009) [114]	Cross-sectional survey	CAM usage patterns	Singaporean adult cancer patients	Outcomes:
				High prevalence of CAM use, influenced by cultural factors.
				Limitations:
				Single-center study.
				Potential selection bias.
				Limited generalizability to musculoskeletal care.
Sperber (2010) [120]	Theoretical review	The “Guru Effect” in alternative beliefs	N/A	Outcomes:
				Proposed mechanism for why people trust incomprehensible ideas from perceived authorities.
				Limitations:
				Lack of empirical testing.
Wolfe, Michaud (2010) [122]	Observational study	Hawthorne effect in clinical trials	Patients with rheumatoid arthritis (RA)	Outcomes:
				Patients showed improved outcomes during the screening process before receiving any treatment.
				This effect led to an overestimation of treatment efficacy in clinical trials.
				Limitations:
				Study based on observational data, which may limit causal inferences.
				Potential confounders are not fully controlled.
				Generalizability to other conditions or trial designs may be limited.
Berthelot et al. (2011) [121]	Commentary	Hawthorne effect vs placebo effect	N/A	Outcomes:
				Argued Hawthorne effect may be stronger than placebo in some cases.
				Limitations:
				Limited empirical evidence presented.
Walach (2013) [90]	Book chapter/review	Placebo effects in CAM	General population	Outcomes:
				Discusses the role of placebo effects in CAM, suggesting that these effects may be particularly strong in CAM due to the holistic approach and strong therapeutic relationships.
				Proposes that CAM might trigger self-healing responses through various contextual and psychological factors.
				Limitations:
				Not peer-reviewed research.
				May lack the rigorous methodology of a systematic review or meta-analysis.
				The generalizability of the conclusions may be limited due to the diverse nature of CAM practices.
Benedetti et al. (2013) [98]	Experimental	Pain perception and opioid/cannabinoid systems	Healthy volunteers	Outcomes:
				Changing pain meaning from negative to positive activates opioid and cannabinoid systems.
				Limitations:
				Small sample size.
				laboratory setting.
Yarritu, Matute (2015) [104]	Experimental	Causal illusion in health beliefs	University students	Outcomes:
				Prior knowledge can induce an illusion of causality through biased behavior.
				Limitations:
				Artificial laboratory task.
Blanco (2017) [102]	Book chapter/Review	Cognitive bias	General population	Outcomes:
				Defined and described various cognitive biases.
				Limitations:
				Not original research.
				Not peer-reviewed research.
Stub et al. (2017) [118]	Qualitative interviews	Complementary therapists’ reflections on practice	Norwegian CAM practitioners	Outcomes:
				Therapists often refer to “patient healing power” as placebo effect.
				Limitations:
				Small sample.
				Potential social desirability bias.
Galbraith et al. (2018) [112]	Systematic review	Traits and cognitions associated with CAM use/belief	CAMs user	Outcomes:
				Identified personality traits and cognitive styles linked to CAM use.
				Limitations:
				Heterogeneity in included studies.
Garrett et al. (2019) [119]	Mixed methods	Perceptions of internet-based health scams	UK adults	Outcomes:
				Identified factors promoting engagement with online health scams.
				Limitations:
				Potential selection bias in online sample.
Moreno Castro et al. (2019) [101]	Qualitative research methods	Influences on perception of pseudo-therapies	Spanish population	Outcomes:
				Media, social circles, and education influence pseudo-therapy beliefs.
				Limitations:
				Self-reported data, potential social desirability bias.
Chow et al. (2021) [105]	Experimental	Causal relationships in pseudoscientific health beliefs	University students	Outcomes:
				Perceived frequency of causal relationships influences pseudoscientific beliefs.
				Limitations:
				Artificial laboratory task.
Rodríguez-Ferreiro et al. (2021) [106]	Experimental	Evidential criteria in pseudoscience believers	Spanish adults	Outcomes:
				Pseudoscience believers have lower evidential criteria.
				Limitations:
				The online sample may not be representative of the general population.
				Self-reported measurements may be subject to bias.
				The study’s correlational nature limits causal inferences about the relationship between evidential criteria and pseudoscientific beliefs.
Davies et al. (2022) [117]	Systematic review	Knowledge used in CAM consultations	Physicians and patients	Outcomes:
				Classified types of knowledge used in CAM practice.
				Limitations:
				Heterogeneity in included studies.
Esteves et al. (2022) [100]	Theoretical paper	Osteopathic care as enactive inference	General population	Outcomes:
				Proposed theoretical framework for osteopathic practice.
				Limitations:
				Lack of empirical testing.
Garcia-Arch et al. (2022) [107]	Experimental	Expert feedback on pseudoscientific beliefs	Spanish adults	Outcomes:
				Expert feedback can increase acceptance of health-related pseudoscientific beliefs.
				Limitations:
				Online sample.
				Artificial task.
García-Arch et al. (2022) [109]	Correlational	Prediction of pseudoscience acceptance	Spanish adults	Outcomes:
				Information interpretation and individual differences predict pseudoscience acceptance.
				Limitations:
				Cross-sectional design, self-reported data.
Piñeiro Pérez et al. (2022) [110]	Cross-sectional survey	Pediatricians’ knowledge and use of CAM	Spanish pediatricians	Outcomes:
				Identified gaps in CAM knowledge among pediatricians.
				Limitations:
				Potential response bias.
Segovia et al. (2022) [9]	Cross-sectional survey	Trust and belief in pseudotherapies	Spanish adults	Outcomes:
				Pseudotherapy use is associated with trust in efficacy rather than belief in scientific validity.
				Limitations:
				Self-reported data.
				Potential social desirability bias.
Torres et al. (2022) [103]	Experimental	Causal illusion in pseudoscientific beliefs	Spanish university students	Outcomes:
				Information interpretation and search strategies influence causal illusions.
				Limitations:
				It does not allow us to know the causality between the illusions of causality and the tendency to maintain unjustified beliefs.
				There may be variables that are not controlled.
Vicente et al. (2023) [125]	Experimental	Prior beliefs’ influence on judgments of medicine effectiveness	University students	Outcomes:
				Prior beliefs influence judgments about both alternative and scientific medicine.
				Limitations:
				The online sample may not be representative, which prevents generalization of the results.
				Potential social desirability bias.
				The correlational nature of the study limits causal inferences.
				The study is based on hypothetical scenarios, which may not fully reflect how people would make decisions in real health situations.
				The study cannot fully control for other factors that might influence judgments about the effectiveness of treatments.
Neogi, Colloca (2023) [123]	Narrative review	Placebo effects in osteoarthritis	Patients with osteoarthritis	Outcomes:
				Placebo effects contribute significantly to pain relief in osteoarthritis.
				These effects are mediated by psychological factors and neurobiological mechanisms.
				Placebo responses may be enhanced by several factors, including the therapeutic encounter, treatment characteristics, and individual patient factors.
				It is suggested that understanding and harnessing placebo effects could improve clinical outcomes and drug development in osteoarthritis.
				Limitations:
				The review is based on existing literature, which may have variable quality and methodologies.
				Generalizability of the findings to all patients with osteoarthritis may be limited.
				The review does not provide new empirical data.
				The long-term effects of placebo responses in osteoarthritis are not well established.