Validation of Catquest-9SF in Danish: developing a revised form of the Catquest-9SF - the Danish Catquest-7SF

Patient-reported visual function outcomes in immediately sequential versus delayed sequential bilateral cataract surgery

PURPOSE

To compare patient-reported visual function outcomes of immediate sequential bilateral cataract surgery (ISBCS) and delayed sequential bilateral cataract surgery (DSBCS).

METHODS

Single-center, randomised controlled trial of patients eligible for bilateral cataract surgery allocated to ISBCS or DSBCS. Patients filled out the Catquest-7SF questionnaire before surgery, 1 week after surgery, and 3 months after surgery.

RESULTS

Ninety-eight patients were included for analysis (ISBCS = 51; DSBCS = 47). In both groups, there was a statistically significant improvement in Catquest-7SF patient-reported outcomes after surgery (p < 0.001), and no difference between the ISBCS and DSBCS groups (p ≥ 0.424). At both 1 week and 3 months post-surgery, a statistically significantly higher proportion of patients were "very satisfied" with the surgical approach in the ISBCS group (94.1% at both 1 week and 3 months) compared to the DSBCS group (55.3% at 1 week and 63.8% at 3 months), both p < 0.001.

CONCLUSIONS

Both ISBCS and DSBCS are effective options to treat bilateral cataracts with no statistically significant difference in patient-reported vision outcomes. However, we found postoperative satisfaction with the surgical approach to be higher among ISBCS patients, which suggests that ISBCS-related benefits, such as fewer health care visits and shorter vision rehabilitation, are compelling to patients.

The effect of phacoemulsification on visual function among Filipino cataract patients measured by a validated Filipino translation of Catquest-9SF

BACKGROUND

This study developed a validated Filipino version of the Catquest-9SF and administered it to cataract patients pre- and post- surgery.

METHODS

This is a two-phase, single-center, cross sectional, questionnaire type study. The study included participants decked for surgery who are 18 years and above. Sampling was done purposively. The Catquest-9SF questionnaire was translated into Filipino, according to a standard procedure, and validated. The validated version was administered to the participants before and after unilateral cataract surgery. Data were analyzed using Rasch analysis.

RESULTS

Sixty-one patients were enrolled in the study. The preliminary Rasch analysis showed misfit of item 2, which was subsequently excluded from analysis. The remaining eight items showed person separation index of 2.70, reliability coefficient of 0.88, infit of 0.66 to 1.17, outfit of 0.66 to 1.49, observed raw variance explained by measures of 55.3% and eigenvalues of 1.9, 1.4, 1.2, 1.0 and 0.9. There was slightly poor targeting (mean person location 1.24) and multidimensionality but no evidence of differential item functioning (DIF). High internal consistency of items were observed (Cronbach's alpha ≥ 90). Comparison of responses between pre- and post-surgery showed highly significant marginal homogeneity (p < 0.001).

CONCLUSION

The Filipino translation of Catquest-9SF, the Catquest-8SF-PH, was highly valid. It showed improved perceived visual outcomes among Filipino patients post-cataract surgery.

Multi-center validation of Catquest-9SF visual function questionnaire in Ontario, Canada

PURPOSE

To investigate the psychometric performance and responsiveness of Catquest-9SF, a patient-reported questionnaire developed to evaluate visual function as related to daily tasks, in patients referred for cataract surgery in Ontario, Canada.

METHODS

This is a pooled analysis on prospective data collected for previous projects. Subjects were recruited from three tertiary care centers in Peel region, Hamilton, and Toronto, Ontario, Canada. Catquest-9SF was administered pre-operative and post-operatively to patients with cataract. Psychometric properties, including category threshold order, infit/outfit, precision, unidimensionality, targeting, and differential item functioning were tested using Rasch analysis with Winsteps software (v.4.4.4) for Catquest-9SF. Responsiveness of questionnaire scores to cataract surgery was assessed.

RESULTS

934 patients (mean age = 71.6, 492[52.7%] female) completed the pre- and post-operative Catquest-9SF questionnaire. Catquest-9SF had ordered response thresholds, adequate precision (person separation index = 2.01, person reliability = 0.80), and confirmed unidimensionality. The infit range was 0.75-1.29 and the outfit range was 0.74-1.51, with one item ('satisfaction with vision') misfitting (outfit value = 1.51). There was mistargeting of -1.07 in pre-operative scores and mistargeting of -2.43 in both pre- and post-operative scores, meaning that tasks were relatively easy for respondent ability. There was no adverse differential item functioning. There was a mean 1.47 logit improvement in Catquest-9SF scores after cataract surgery (p<0.001).

CONCLUSION

Catquest-9SF is a psychometrically robust questionnaire for assessment of visual function in patients with cataract in Ontario, Canada. It is also responsive to clinical improvement after cataract surgery.

Catquest-9SF questionnaire: Validation in a Greek-speaking population using Rasch analysis

PURPOSE

The Catquest-9SF questionnaire is a tool measuring visual disability and vision-related limitation in patients' daily activities. The primary objective of this study was the validation of Catquest-9SF in a Greek-speaking cataract population.

METHODS

The questionnaire was translated into Greek and translated back into English. A pre-final Greek version was formed and tested by 10 Greek-English bilingual participants and by the translation team, and the final version was produced. Patients scheduled for cataract surgery completed the questionnaire preoperatively and postoperatively. Rasch analysis was performed for the assessment of the Catquest-9SF psychometric properties, including response category ordering, item fit statistics, principal components analysis, precision, differential item functioning and targeting for preoperative and postoperative data collectively.

RESULTS

A total of 100 (55 men, 45 women, mean age = 71.94±6.63) cataract patients completed the Greek version of Catquest-9SF questionnaire preoperatively and postoperatively. Rasch analysis showed a significant improvement in the median person Rasch score from -1.49 preoperatively to -4.71 logits postoperatively, while the effect size was 1.3. Unidimensionality was confirmed since infit and outfit mean square values varied between 0.66 and 1.37. Rasch analysis showed good precision and separation ability (Person Separation Index of 3.28, and Person Reliability of 0.92). Four response categories were found for all items. The item-person means difference was -1.83 logits. The difference between preoperative and postoperative Catquest-9SF logit score was positively correlated with preoperative Catquest-9SF logit score (coeff. = 0.798, p<0.0001) and negatively correlated with postoperative spherical equivalent (coeff. = -0.825, p = 0.011).

CONCLUSION

The Greek version of Catquest-9SF proved to be reliable, valid, unidimensional and responsive to changes after cataract surgery presenting good psychometric properties for cataract patients. Some postoperative mistargeting was found indicating that the tasks were easily performed by respondents after cataract surgery.

TRIAL REGISTRATION

NCT05323526 -retrospectively registered.

Self-assessed visual function outcome in cataract surgery: minimum important difference of the Catquest-9SF questionnaire

BACKGROUND

The purpose of this study was to study the minimum important difference (MID) of the Catquest-9SF questionnaire in cataract surgery.

METHODS

A nationwide multi-center prospective randomized study was conducted using the Swedish National Cataract Register and the Catquest-9SF questionnaire. Randomized patients (n = 400) who had completed the Catquest-9SF before surgery and three months after surgery were sent an anchor question on self-assessed change in visual function after cataract surgery 14 days after the postoperative Catquest-9SF. Rasch analysis was performed on the preoperative and postoperative Catquest-9SF questionnaires, and the patients were dichotomized with regard to their preoperative Rasch score. The MID range of the two groups was calculated based on the anchor question, and the anchor question based MID was then estimated in a scatter plot. The MID was also estimated based on distribution by calculating Cohen's effect size.

RESULTS

The analyses included 231 patients who had completed the Catquest-9SF on both occasions as well as the questionnaire with the anchor question. The group with better preoperative visual function had an anchor question based MID of - 0.5 and a Cohen's effect size based MID of - 1.07. The group with worse preoperative visual function had an anchor question based MID of - 1.80 and a Cohen's effect size based MID of - 1.46.

CONCLUSION

This article contributes detailed knowledge of the MID of Catquest-9SF, enabling even more accurate high-quality evaluation of the outcome and benefit of cataract surgery worldwide.

Evaluation of the Pain Impact Index for Community-Dwelling Older Adults Through the Application of Rasch Modelling

OBJECTIVE

Evaluate the Pain Impact Index, a simple, brief, easy-to-use, and novel tool to assess the impact of chronic pain in community-dwelling older adults.

METHODS

A Rasch modelling analysis was undertaken in Stata using a partial credit model suited to the Likert-type items that comprised the Index. The Index was evaluated for ordering of category thresholds, unidimensionality, overall fit to the Rasch model, measurement bias (Differential Item Functioning, DIF), targeting, and construct validity.

RESULTS

The four-item Pain Impact Index was self-completed by 6454 community-dwelling Australians who were aged at least 70 years and experienced pain on most days. Two items showed evidence of threshold disordering, and this was resolved by collapsing response categories (from 5 to 3) for all items. The rescored Index conformed to the unidimensionality assumption and had satisfactory fit with the Rasch model (analyses conducted on a reduced sample size to mitigate the potential for overpowering: n = 377, P > 0.0125, power > 77%). When considering uniform DIF, the most frequent sources of measurement bias were age, knee pain, and upper back pain. When considering nonuniform DIF, the most frequent source of measurement bias was knee pain. The Index had good ability to differentiate between respondents with different levels of pain impact and had highest measurement precision for respondents located around the average level of pain impact in the study sample. Both convergent and discriminant validity of the Index were supported.

CONCLUSION

The Pain Impact Index showed evidence of unidimensionality, was able to successfully differentiate between levels of pain impact, and had good evidence of construct validity.

Validity of the French version of Catquest-9SF and use of an electronic notepad for entering patient-reported outcome measures

Background

The Catquest-9SF questionnaire is a patient reported outcome measure that quantifies the visual benefits from cataract surgery. The purpose of this study was to translate and adapt the Catquest-9SF questionnaire for France, to assess its psychometric properties via Rasch analysis, and to assess its validity when completed using an electronic notepad.

Methods

The Catquest-9SF questionnaire was translated following the guidelines of the International Society for Pharmacoeconomics and Outcomes Research. Catquest-9SF and clinical data were collected from patients before and after routine cataract surgery. All questionnaire data were collected via an electronic notepad. Rasch analysis was performed to assess psychometric properties, and sensitivity to change was analysed for patients with complete paired pre- and post-operative questionnaires.

Results

A complete filled-in preoperative questionnaire was obtained for 848 patients. Rasch analysis showed good precision (person separation: 2.32, person reliability: 0.84), ordered category probability curves, no item misfit, and unidimensionality. The respondents were slightly more able than the level of item difficulty (targeting: −1.12 logits). Sensitivity was analysed on 211 paired questionnaires, and the postoperative questionnaires showed a clear ceiling effect. The effect size was 2.6. The use of an electronic notepad for completing the questionnaire worked out very well after some adjustments.

Conclusions

The French version of Catquest-9SF has good psychometric properties and is suitable for use in French-speaking patients. The use of the Catquest-9SF questionnaire in an electronic format showed good validity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-021-00233-7.

Catquest-9SF questionnaire and eCAPS: Validation in a Canadian population

Background

Visual acuity alone has limitations in assessing a patient’s appropriateness and prioritization for cataract surgery. Several tools, including the Catquest-9SF questionnaire and the electronic cataract appropriateness and priority system (eCAPS) have been developed to evaluate patients–reported visual function as related to day-to-day tasks. The aim of this study was to validate Catquest-9SF and eCAPS in a Canadian population and propose a shorter version of each, in an attempt to extend their applicability in clinical practice.

Methods

The English translation of the Swedish Catquest-9SF and eCAPS were self-administered separately in pre-operative patients in tertiary care in Peel region, Ontario. Rasch analysis was used to validate both scales and assess their psychometric properties, such as category threshold order, item fit, unidimensionality, precision, targeting, and differential item functioning.

Results

A total of 313 cataract patients (mean age = 69.1, 56.5% female) completed the Catquest-9SF and eCAPS. Catquest-9SF had ordered response thresholds, adequate precision (person separation index = 2.09, person reliability = 0.81), unidimensionality and no misfits (infit range 0.75–1.35, outfit range 0.83–1.36). There mean for patients was equal to -1.43 (lower than the mean for items which is set automatically at zero), meaning that tasks were relatively easy for respondent ability. eCAPS had 3 items that misfit the Rasch model and were excluded (infit range 0.82–1.30, outfit range 0.75–1.36). Precision was inadequate (person separation index = 0.19, person reliability = 0.04). 78.8% of subjects scored≤9 (answered that they had no issues for most questions).

Conclusions

Catquest-9SF demonstrated good psychometric properties and is suitable for assessing visual function of care-seeking patients referred for cataract surgery in Ontario, Canada. There was some mistargeting, suggesting that the tasks were relatively easy to perform, which is consistent with previous research. On the contrary, eCAPS is not sensitive in differentiating patients who had impaired visual functioning.

Validation and application of Catquest-9SF in various populations: A systematic review

Cataract is a common cause of reversible blindness. Visual acuity alone is not enough to assess appropriateness for surgery, prioritization, and outcomes. Catquest-9SF questionnaire evaluates patients' self-assessed visual function as related to daily tasks. We summarize and assess the validity of Catquest-9SF as a patient-reported outcome questionnaire to determine its suitability for clinical use. Thirteen studies with sample sizes ranging 102-10,886 (total n = 15,289) undertaken from 2009 to 2018 were included. Catquest-9SF showed unidimensionality, ordered response thresholds, and acceptable precision in all studies. Nine studies had significant mistargeting (range 0.66 to -2.04); the tasks being easy relative to the respondent ability in most studies. Two studies had misfitting items. We conclude Catquest-9SF is a valid and reliable tool to measure visual function in patients with cataract in various populations. Because results can be population specific, it is recommended that Catquest-9SF be validated in a new population before it is incorporated in routine practice.