OBJECTIVES: To assess the benefits and harms of TENS for managing pain in people with SCD who experience pain crises or chronic pain (or both).

SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Register, comprising of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also searched online trial registries and the reference lists of relevant articles and reviews. Date of the last search: 26 Febraury 2020.

SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs, where TENS was evaluated for managing pain in people with SCD.

DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the eligibility of the trials identified by the literature searches according to the inclusion criteria. Two review authors then independently extracted data, assessed for risk of bias using the Cochrane standard tool and rated the quality of evidence using the GRADE guidelines.

MAIN RESULTS: One double-blind cross-over RCT with 22 participants with SCD (aged 12 to 27 years) was eligible for inclusion. Following stratification into four pain crises severity grades, participants were then randomised to receive TENS or placebo (sham TENS). The trial was concluded after 60 treatment episodes (30 treatment episodes of each treatment group). There is a lack of clarity regarding the trial design and the analysis of the cross-over data. If a participant was allocated to TENS treatment for an episode of pain and subsequently returned with a further episode of a similar degree of pain, they would then receive the sham TENS treatment (cross-over design). For those experiencing a pain episode of a different severity, it is not clear whether they were re-randomised or given the alternate treatment. Reporting and analysis was based on the total number pain events and not on the number of participants. It is unclear how many participants were crossed over from the TENS group to the sham TENS group and vice versa. The trial had a high risk of bias regarding random sequence generation and allocation concealment; an unclear risk regarding the blinding of participants and personnel; and a low risk regarding the blinding of the outcome assessors and selective outcome reporting. The trial was small and of very low quality; furthermore, given the issue with trial design we were unable to quantitatively analyse the data. Therefore, we present only a narrative summary and caution is advised in interpreting the results. In relation to our pre-defined primary outcomes, the included trial did not report pain relief at two to four weeks post intervention. The trial authors reported that no difference was found in the changes in pain ratings (recorded at one hour and four hours post intervention) between the TENS and the placebo groups. In relation to our secondary outcomes, the analgesic usage during the trial also did not show any difference between groups. Given the quality of the evidence, we are uncertain whether TENS improves overall satisfaction as compared to sham TENS. The ability to cope with activities of daily living was not evaluated. Regarding adverse events, although one case of itching was reported in the TENS group, the site and nature of itching was not clearly stated; hence it cannot be clearly attributed to TENS. Also, two participants receiving 'sham' TENS reported a worsening of pain with the intervention.

MATERIALS AND METHODS: A randomised controlled trial (RCT) study involving 111 undergraduate medical students was conducted where the competency of skills was assessed by objective structured clinical examination (OSCE) in the first, fourth and seventh/eighth weeks. A cohort of 12-14 students was enrolled for each session. The randomisation of the participants into control (VAL-based teaching) and intervention (HFS-based teaching) groups was achieved by implementing the computer-based random sequence generation method. VAL-based teaching module was a fully interactive face-to-face teaching session where a prerecorded video clip was used. The video clip detailed the diagnosis of tension pneumothorax in an acute medical emergency and its management by performing needle decompression on a high-fidelity patient simulator (METIman). HFS-based teaching module was delivered as a fully interactive hands-on training session conducted on the same METIman to demonstrate the diagnosis of tension pneumothorax in an acute medical emergency and its management by performing needle decompression. OSCE scores were compared as the denominator of learning (enhancement and retention of skills) between two groups who underwent training with either VAL-based or HFS-based teachings. The OSCE assessments were used to evaluate the participants' performance as a group. These scores were used to compare the enhancement and medium-term retention of skills between the groups. The outcome was measured with the mean and standard deviation (SD) for the total OSCE scores for skills assessments. We used General Linear Model two-way mixed ANOVA to ascertain the difference of OSCE marks over assessment time points between the control and the intervention groups. ANCOVA and two-way mixed ANOVA were used to calculate the effect size and the partial Eta squared. p value less than 0.05 was taken to be statistically significant.

RESULTS: The two-way mixed ANOVA showed no statistically significant difference in mean OSCE scores between intervention and control groups (p=0.890), although the mean score of the intervention group was better than the control group.