**2. The quality of evidence**

While it is critical for acupuncture practitioners to understand the effects of acupuncture, they frequently have concerns about which conditions (diseases) acupuncture therapy has had the most evidence of benefit and the least risk to their patients. Guidelines were already being published at a higher rate than before. Acupuncturists should understand how guidelines are developed to make effective choices concerning health care. The GRADE approach has been adopted by national and international organizations that develop guidelines for acupuncture practitioners. GRADE is a system for assessing the quality of available evidence that supports acupuncture therapy for patients with a variety of conditions. The evidence was categorized as being of high, moderate, low, or very low quality [5]. The study design is critical in determining the quality of the evidence. Randomized controlled trials (RCTs) are initially given a higher grade due to their generally lower susceptibility to bias [6] than observational studies [7]. RCTs will be degraded since they have a bias that can be identified [8]. When multiple high-quality studies show consistent results, observational studies can be upgraded [9]. Factors that can lead to downgrading the quality of evidence: risk of bias: a lack of randomization, allocation concealment, and blinding biases; inconsistency: the results of different trials show significant and unexplained variation; indirectness of evidence: a comparison of a population, outcome, or intervention that is not direct; imprecision: wide confidence intervals reduce the data's quality; publication bias: studies with "negative" results are not published. Factors that can lead to an upgrade: large effect: the effect is so large that common biases in observational studies cannot possibly explain the result; dose-response relationship: the outcome is proportional to the amount of exposure. All plausible biases only reduce an apparent treatment effect: all possible confounders would only serve to dilute the effect that was observed [10]. GRADE levels do not always imply a recommendation, and the GRADE process is differentiated from the recommendation process. Although a high level of evidence is more likely to result

#### **Figure 1.**

*Recommendation steps using the GRADE method.*

in a recommendation, in some cases, a low or very low level of evidence can lead to a strong recommendation [11]. Other factors, such as cost, clinical judgment, and patient preference, must be considered in the development of recommendations, in addition to the quality of evidence [12]. Acupuncture practitioners will be able to make better clinical decisions if they understand the GRADE method [5]. There are five steps to the GRADE process, which we explain with examples in **Figure 1**.
