From: Mindfulness-based interventions in epilepsy: a systematic review
Thompson et al. (2010) [34] | Thompson et al. (2015) [35] | Tang et al. (2015) [36] | ||||
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Entry | Judgement | Support for judgement | Judgement | Support for judgement | Judgement | Support for judgement |
Random sequence generation (selection bias) | Unclear Risk | Quote: “Using a stratified randomized, crossover design we randomly assigned participants to one of four strata.” Randomisation method is not described | Unclear Risk | Quote: “Using a stratified randomized, crossover design we randomly assigned participants to one of four strata.” Randomisation procedure not described | Low Risk | Quote: “Simple randomization by drawing was performed within each block to assign patients to one of the groups alternatively” Random allocation |
Allocation concealment (selection bias) | Unclear Risk | Unclear whether participants/assessors could have been aware of allocation to intervention/control in advance | High Risk | Quote: “…within each condition, people who required a particular mode of delivery (web or telephone) were placed in that group and the remainder (the majority of participants) were assigned to equalise the groups.” Not described, appears patients were allocated to different interventions (web or telephone) based on preference/need | Unclear Risk | Quote: “randomization was performed by an independent research assistant” Randomization performed by independent research assistant but method of concealment not explained. |
Blinding of participants and personnel (performance bias) | High Risk | Quote: “Neither the participants nor the project staff were blinded to the group assignment.” Clearly stated in paper under 2.5.3 Recruitment that neither were blinded | High Risk | Not described, and as above participants could choose to receive telephone or web delivery. | Low Risk | Quote: “A team of trained research assistants…who were blinded to participants’ intervention group performed all assessments…” The assessors were blinded to the patient’s intervention grouping. |
Blinding of outcome assessment (detection bias) | High Risk | Quote: “Neither the participants nor the project staff were blinded to the group assignment.” Clearly stated in paper under 2.5.3 Recruitment that neither were blinded | Unclear Risk | Not described | Low Risk | Quote: “…team of trained research assistants with a bachelor’s degree in psychology who were blinded to participants’ intervention group performed all assessments; they were separated into 2 teams, one for baseline assessment and the other for post intervention assessment.” |
Incomplete outcome data addressed (attrition bias) | High Risk | Due to repeated measures design only participants completing interim assessments were included in analyses. 13 participants left the study, not clear if control or intervention. Missing data not described | Unclear Risk | Attrition poorly characterised. Attendance poorly described including reasons for not attending. Missing values were imputed, but levels of missing values were not described. However intention-to-treat analysis carried out according to participants’ original treatment assignment. | Low Risk | Missing outcome data balanced in numbers across intervention groups. |
Selective reporting (reporting bias | Unclear Risk | All outcomes appear to have been reported, however no protocol. | Unclear Risk | Primary outcome not defined and poor discussion of four of six main outcomes (DCSE, SC, Physical and mental health QoL). No protocol. | Low Risk | Full study protocol is available |
Other Bias | Unclear Risk | Unclear Risk | Low Risk | No other sources of bias |