3.1 study selection.
An initial search of RCTs yielded 621 potential literature citations (Fig. 1). After screening, 611 articles were excluded and 10 articles were examined in detail to assess their relevance.
3.2 overall study characteristics
A total of 12 studies met the inclusion criteria and were included in our studies. Two of the relevant outcome indicators could not be combined for statistical analysis and could not be included in quantitative studies. All the studies were performed in china. The characteristics of the studies were showed in Table 1.
3.3 Methodological quality and risk bias evaluation of the studies
The methodological quality and risk bias assessment results of the included quantitative research are moderate. Random number table method was used in all the studie. Three studies used closed envelopes for random allocation. Since the control group used conventional analgesic nursing interventions or drug interventions, and did not use fake acupuncture or body acupuncture treatment, the participants and Blindness of patients is not suitable for WAA intervention, so the risk of bias in all studies is high. Only one study reported blinded methods for evaluating results. The methodological quality evaluation of the included studies is shown in Fig.2 a, and the risk bias evaluation is shown in Fig.2 b.
3.4 Results of Meta analysis
3.4.1 Analgesic effect analysis base on VAS
3.4.1.1 pure WAA group
Based on the VAS analgesic effects, four studies (10)reported that the pain score is lower in ankle acupuncture group (Fig.3 a). The difference was statistically significant [MD= -0.29,95%CI(-0.37,-0.21),P<0.0001]. The funnel chart (Fig.3 b) shows that the distribution of the literature included in the study's pain score comparison is still symmetrical, indicating that the bias is at an acceptable level and the analgesic effect of the wrist-ankle acupuncture group is better than that of the non-wrist-ankle acupuncture group.
3.4.1.2 combined with other therapies
The analgesic effect was compared in four studies(11). According to the results(Fig.4 a), the pain score in the WAA combined with other therapies group was lower than that of the non-WAA group, and the difference was statistically significant [MD= -0.16,95%CI(-0.30,-0.02),P=0.02]. The funnel chart (Fig.4 b) shows that the distribution of the literature included in the study's pain score comparison is still symmetrical, indicating that the bias is at an acceptable level, and the analgesic effect of the wrist-ankle acupuncture combined with other therapies is better than that of the non-wrist-ankle acupuncture group.
3.4.1.3 Comparison of analgesic dosages
Two studies(12) compared the dosage of analgesic drugs, and 133 patients were included in the studies, including 65 in the experimental group and 68 in the control group. The results (Fig.5 a) showed that compared with non-WAA group, the application of WAA can reduce the used of analgesic drugs, and the difference is statistically significant [MD= -0.33,95%CI(-0.57,-0.09),P=0.008].
3.4.1.4 Analgesia satisfaction
Three studies(13) compared the .satisfaction of analgesia effect after using WAA and 222 patients were included, 111 in experimental group and 111 in the control group. The results (Fig.5 b)showed that the analgesic satisfaction of the WAA group was higher than that of the non-wrist-ankle acupuncture group, and the difference was statistically significant [OR= 4.23,95%CI(1.35,13.24) ,P=0.01].
3.1.1.5 Adverse Events Reporting
Seven studies (14)clearly reported adverse events. 485 patients were enrolled, including 242 in the experimental group and 243 in the control group. The adverse reaction rates were lower in the experimental group, and the difference was statistically significant (Fig.5 c) [OR= 0.25,95%CI(0.15,0.41) , P<0.0001]. The main adverse reactions in the WAA group were subcutaneous hemorrhage and fainting needles. The adverse reactions in the conventional analgesic care group were nausea and vomiting, urinary retention, dizziness and drowsiness.