Walter 2005.

Methods	Study design: RCT Study grouping: parallel group, involving 29 people (58 eyes), where both eyes received the same type of IOL but no further details are provided in relation to the statistical approach Exclusions after randomisation: not reported Losses to follow‐up: not reported How missing data were handled: not reported Reported power size calculation? no
Participants	Baseline characteristics Blue‐light filtering IOL group Number of participants: number of people (number of eyes): not reported Sex (number of women/number of men): not reported Age (mean ± unit of error): not reported Non‐blue‐light filtering IOL group Number of participants: number of people (number of eyes): not reported Sex (number of women/number of men): not reported Age (mean ± unit of error): not reported Inclusion criteria: non‐amblyopic bilateral cataract patients aged 60‐80 years with inconspicuous (normal) colour recognition test (Ishihara) Exclusion criteria: not reported Comparison of study groups at baseline: not reported
Interventions	Intervention characteristics Blue‐light filtering IOL Type of IOL: AF‐1 (UY) YA‐60BB (Hoya) Non‐blue‐light filtering IOL Type of IOL: AF‐1 (UV) VA‐60BB (Hoya)
Outcomes	Visual acuity, contrast sensitivity and colour vision at six weeks and four and a half months postoperatively
Identification	Sponsorship source: Funding sources: not reported Declaration of interest: not reported Country: Germany Setting: not reported Comments: Date study conducted: not reported Trial registration number: not reported Contacting study investigators: study authors not contacted; no additional information used for review First author's name: S Walter Institution: Universitäts‐Augenklinik Magdeburg, Germany Email: Not reported Corresponding author's address: not reported
Notes	Conference abstract, in German
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Judgement comment: not reported how list was generated. Study is described as “randomised” but with no further details
Allocation concealment (selection bias)	Unclear risk	Judgement comment: not reported how allocation administered. Study is described as “randomised” but with no further details
Blinding of participants and personnel (performance bias) All outcomes	High risk	Judgement comment: study described as open label
Blinding of outcome assessment (detection bias) All outcomes	High risk	Judgement comment:study described as open label
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Judgement comment: follow‐up not reported
Selective reporting (reporting bias)	Unclear risk	Judgement comment: no access to protocol or trials registry entry
Other bias	Unclear risk	Judgement comment: insufficient information within abstract to judge other potential sources of bias