These two research methodologies, quantitative and qualitative, generally polarize along the objective (quantitative) and subjective (qualitative) continuum, yet Park and Ernst's study has aspects of both.
They summarize their study as "a systematic review of all randomized controlled trials (RCTs) on the effectiveness of Ayurvedic medicine for RA." Thus, it is qualitative in nature. However, their research design and meticulous literature search are consistent with quantitative studies - structured, repeatable, well documented and theory based.
The integrity of a literature study depends on the integrity of trial selection. Biased trial selection can bias the study. The authors took noteworthy precautions to ensure the study's integrity. They found only seven RCTs meeting their inclusion criteria:
After their comprehensive search, the authors indicate they identified 33 trials. This is a satisfactory sample size, but their review revealed trials with methodological concerns, particularly non-randomization, observational structures, or lacking controls. Once these trials were excluded, they had a sample size of seven. The seven selected, meeting the strict inclusion criteria, were methodologically sound. They incorporated important tenets of scientific research, being systematic, controlled, and empirical.
The authors detailed their team's search strategy including:
Electronically searching major databases (Medline, Embase, AMED, Cochrane Controlled Trial Register, and the abstract service of Central Council for Research in Ayurveda and Siddha [CCRAS])
Hand searching 4 relevant Sri Lankan and Indian journals not in the electronic databases
Electronically and hand searching the authors' personal files
Further, they detailed their keyword selection for the searches and indicated imposing no language restrictions.
Documenting that trial selection was predicated upon documented keywords reduced the potential for both overt and covert bias, enhancing objectivity while minimizing subjectivity. Documenting that trial selection was performed scientifically and not according to the authors' personal choices allows the reader to better interpret the information as they see fit, rather than reading a study that reflects the authors' opinions.
To further educate readers, Park and Ernst provide a comprehensive paragraph on how they scored and reviewed the articles. In addition to ensuring that each article was reviewed by a person speaking the language of the trial article, they noted that they followed the QUOROM guideline for systematic reviews and used a standardized score (Jadad) for assessing methodological quality.
The authors document scientifically why they believed the study of value