Quality assessment of randomised controlled trial studies reporting delirium
| Study | Randomisation | Concealment of allocation | Similarity at baseline | Blinding of outcome assessor | Incomplete outcome data (for outcome of delirium) | Validity of assessment tool | Assessment tool specific for delirium | Selective reporting |
| Risk of bias described as LOW, UNCLEAR or HIGH | ||||||||
| Neuman et al 201639 | UNCLEAR | UNCLEAR | Groups similar for age, gender and comorbidities | LOW | LOW | CAM good validity for identifying delirium | Yes | UNCLEAR |
| n=12 (Letter) | No details | Blinded research coordinators assessed outcomes | Results reported for all patients | Insufficient information to permit judgement | ||||
| Parker and Griffiths 201538 n=322 | UNCLEAR | LOW | Groups similar for all baseline characteristics measured, except for proportion of male patients (35% in GA group, 19% in RA group) | HIGH | LOW | Unclear—no details | UNCLEAR | UNCLEAR |
| Randomisation undertaken by opening sealed opaque numbered envelopes prepared by a person independent to the trial | No blinding of outcome assessors | Appears postoperative delirium measured in all patients allocated to respective treatments | Insufficient information to permit judgement | |||||
| Casati et al 200336 | UNCLEAR | LOW | Groups similar for all baseline characteristics measured | UNCLEAR | LOW | MMSE good validity for cognitive function | No | UNCLEAR |
| n=30 | “Using a sealed envelope technique, patients were randomly allocated…” | Clinical criteria for patient’s discharge applied by staff blinded to anaesthetic technique—but no details for applying MMSE | MMSE for all 30 patients at 1 and 7 days | Insufficient information to permit judgement | ||||
| Bigler et al 198535 | UNCLEAR | UNCLEAR | Groups similar for all baseline characteristics measured except for vasopressors being administered more frequently in spinal group | LOW | UNCLEAR | AMT good validity for cognitive dysfunction | No | UNCLEAR |
| n=40 | No details (other than “patients randomly allocated”) | No details | Surgeon undertaking AMT unaware of anaesthesia given | No details on proportion that AMT was undertaken in at 7 days and 3 months | Insufficient information to permit judgement | |||
Quality assessment was not performed for Kamitani et al 37 as a full translation was not available. Blinding of patients and surgeons/anaesthetists not possible.
AMT, Abbreviated Mental Test; CAM, confusion assessment method; GA, general anaesthesia; MMSE, Mini–Mental State Examination; RA, regional anaesthesia.