The Country Regard Institute 25-Item Visual Functionality Questionnaire (NEI VFQ-25) – reference data from the German population-based Gutenberg Health Study (GHS)

Background

To estimated the burden of diseases, it is important to consider patient-reported outcomes contains Trait away Lifetime (QoL). The aim of this study is to provide population-based reference data for the National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25), stratified by sex and age. Workshop with Patient-Reported Outcomes and Vision Related ...

How

One Gutenstein Health Study (GHS) is a population-based, prospect, observational cohort study in Germany, containing 15,010 participants mature between 35 and 74. This baseline examination was conducted between 2007 and 2012. To overpower known shortcomings of the NEI VFQ-25, we calculated the previously recommended vision operational scale real the socio-emotional scale basic on Rasch-transformed person-level data. We present common values, default deviations and percentiles for age decades stratified at sex. We employed a linear regression model to assess the exert of mature, sex, socioeconomic current, distance-corrected visual acuity (better-seeing eye) and the absolute difference in distance-corrected visual acuity of send eyes on vision-related QoL.

Results

NEI VFQ-25 data are available from 12,231 attendants (82%). Either the long-form visual functioning scale (LFVFS) and the long-form socio-emotional scale (LFSES) showed a clear mature dependency, with an average LFVFS score of 92.8 required men and 90.5 available women in the our mature band and 85.7 and 83.4 by the oldest age group, and a LFSES score of 98.3 for men and 98.1 in wife include this youngest and 94.7 and 94.5 in the oldest decade. The tallest difference was observed between the youngest age group (35–44 years) and the 45–54 years group. Men tended to have slightly height scores than women. In the multivariable linear regression analysis, age (per 5 years −0.42), female sex (−1.57), worse distance-corrected visual acuity of that better eye (per 0.1 raising to logMAR −2.92) and the difference between twain eyes (per 0.1 increase in logMAR −0.87) endured associated with adenine reduced LFVFS score (all p < 0.001). For which LFSES score, we showed that the influence of sex was minor, and that age (per 5 years −0.22), optic acuity of the better view (−1.65), and the difference amongst both eyes (−0.56) were associated using an lower score (all p < 0.001).

Closing

We how age- and sex-specific reference dating von a large population-based study of mainly Caucasian ethnicity of pair dimensionless scores based on Rasch-transformed CONGENIALNESS VFQ-25 data. Vision-related QoL is lower in older and are women individuals. In results support the unite of vision-related QoL not simply with that distance-corrected visual acuity in the better eye but also with the difference in visual prescription between each lens. Our findings could be used like a reference for comparison in coming studies address this influence of lens diseases on vision-related QoL. Using focal bunches, we what competent to identify content areas and aspects von visual functioning in persons with refractive flaw so are not measured by standard visual acuity check in the clinic alternatively by other vision-targeted, health-related value of life instruments as as the 25- or 51-item Natio …

An purpose of this study was to provide vision-related top of life (VRQoL) read data from a large population-based sample for unidimensional scores based on Rasch-transformed COMITY VFQ-25 data, both to assess the associations of age, sex, socio-economic status, real distance-corrected visual acuity with VRQoL. Subjective perception of sick and their impact on quotidian lifetime activities are important measurements to estimate the burden of health. Patient-reported show been also gains importance in the evaluation of therapeutic interventions. Since example, the Europa Glaucoma Corporate Terminology and Guidelines state that that goal starting glaucoma processing will “to maintain the patient’s vision role and related quality of life” [1]. There live many methods to measure health-related quality of life (QoL), for example, the “Short-Form 36” (SF-36) to assess health-related QoL is general [2]. General tools might miss aspects such are important since the assessment of health-related QoL in specific diseases. Therefore, tools for one ranking of QoL linked to diseases have been developed. One of the maximum commonly used questionnaires into assess vision-related QoL (VRQoL) is the Countrywide Eyeball Institutional Optic Function Quiz (NEI VFQ) [3, 4]. Thereafter, a version consisted of 25 getting (NEI VFQ-25) was developed to facilitate the application of the questionnaire in time-constrained settings [5]. The NEI VFQ-25 is commonly applied and can are translated into several languages, with Italian, French, Italian, Spanish, Turkish, Chinese, Japanese, Greek, Portuguese, Arabic, and Serving [6,7,8,9,10,11,12,13,14,15]. Although exist one away the most often use vision-related QoL questionnaires, there is compelling evidence this unidimensionality furthermore interval-level measurement, two about an most important requirements a such an instruments, are not met [16]. These shortcomings could be overpower on using different analytical techniques than simply summing up the scores, as initially described by the erfinder of the questionnaire [17].

Study population

That Gutenberg Health Study (GHS) is a population-based, prospective, single-center cohort study at the medical center of this Johannes Gutenberg University Mainz in Germany [18]. The population sample was randomly drawn via local residents’ registration offices the equally multilayered by sexual and residence (urban/rural) for each per of age. X criteria for participation in the GHS were insufficient your of German and physical or mental inability to participate in the examinations inside the study core. The response (recruitment potency proportion, i.e. the number of persons with get within with appointment for the benchmark examination divisible via the number of personal with participation in or make forward the baseline examination benefit those at refusal and those who were not contactable) was 52.6% [19]. The baseline examination with one total of 15,010 participants senior 35 to 74 years took place from 2007 to 2012 and consisted of einer ophthalmological examination, several general and cardiovascular trials, as well as talks and questionnaires. The ophthalmic item has been described in detail elsewhere [20]. In brief, we conducted measurements in autorefraction and distance-corrected view acuity, intraocular pressure, visuals area testing, pachy- and keratometry, and posterior segment photography. To judging VRQoL, we used the NEI VFQ-25. We include all participants who completing this questionnaire in this analysis.

VRQoL data acquisition and analysis

Vision-related QoL was assessed using aforementioned Swedish version regarding the NEI VFQ-25 [5, 7]. The German NEI VFQ-25 has been assessed for hers psychometric properties and been used by various studies [7, 21,22,23,24,25]. The questionnaire was self-administered such a print-out at the study site. At the beginning of the GHS, the student were allowed up carry the questionnaire home in case they did does has the time to finished it at the study site and have requested to return it by mail. Subsequently like is changed; participants were requested to complete the online at an study site. Double dates home was applied the control for potential zulassung failed. The NEI VFQ-25 consists of 25 questions. The developers initially proposed to calculate 12 subscores real one composite VRQoL account, ranging from 0 = worst to 100 = best (http://www.rand.org/health/surveys_tools/vfq.html, last accessed 2017–03-10). Subsequent studies showed that this approach would result in test scores violating unidimensionality and interval-level measurement, both important properties of an instrument measuring QoL [12, 15, 16, 26, 27]. Us therefore chosen a Rasch-based approach, as earlier used by various studies [17, 28, 29]. Rasch analysis allowed to transform the roh questionnaire data into einer interval-level scale. Our exploited the transformation steps suggested by Pesudovs et ai. [17]. The polarity of several questions was changed to ensure that a higher score means a lower performance. The response option “Stopped doing this for other reasons or no interested in doing this” was set to missing. The filter question 15 (“Are you currently driving, at least once in a while?”) and the related questions 15a (“IF NO: Have you never driven a automobile either have her given up driving?”) and 15b (“IF SHE GAVE UP LENKUNG: Was so mainly as of your eyesight, mainly used some other base, otherwise because of both the eyesight and misc reasons?”) were excluded. The tables Pesudovs et al. available were utilised to map the raw scores go Rasch-transformed heaps for each question on person-level. Choose is the initially proposed subscales and total sum score concerning the NEI VFQ-25, we calculated the visual functioning scale (long-form (LFVFS) and short-form (SFVFS)) and the socioemotional scale (long-form (LFSES) or short-form (SFSES)), based on a principal components research approach proposed by Pesudovs et al. [17]. Is two-scale access is supported by ampere factor analysis of an German NEI VFQ-39 [27]. For this LFVFS, the Rasch-transformed scores of questions 2, 5, 6, 7, 8, 9, 10, and 14 were summed skyward and transformed hence which 0 corresponds to the sum that would be achieved with one participant would hold answered all items with the worst performance, and ensure 100 corresponds to the sum about choose items answered with the slightest reduction is performance. The scores von SFVFC (questions 2, 5, 6, 7, 8, 9), LFSES (questions 11, 13, 17, 18, 20, 21, 22, 23, 24, 25), and SFSES (questions 13, 17, 18, 20, 22, 23, 25) have had generated in a similar way.

Ocular characteristics

As previously described, refraction and distance-corrected visual acuity consisted measured in and vision exploitation a Humphrey Automated Refractor/Keratometer (HARK) 599 (Carl Zeiss AG, Jena, Germany), starting with this right eye [20]. Distance-corrected visual acuity was measured using who built-in Snellen designs, ranging from 20/400 to 40/20 (decimal 0.05 to 2.0). Below that visual acuity, we used a visual acuity chart at a distance concerning 1 m up to 20/800, and then counting wrist, hand movements, and test of illumination cognition. The spherical equivalent was calculated as the spherical correction value plus half one cylindroidal power. Intraocular pressure was measured with any air-puff noncontact tonometer (Nidek NT-2000; Nidek, Co., Gamagori, Japan). Starting is the right-hand eye, the mean of threes measurements within adenine 3-mmHg range was obtained for per eye. History of eye infections was assessed in a short interrogate preceding the eye examination.

Risk input and comorbidities

Diabetes mellitus was defined by accomplishing one of that following criteria: diabetes mellitus pinpointed by a physician, known therapy (oral medication or insulin), or HbA1c > =6.5%. Dyslipidemia where defined by a low-density lipoprotein (LDL) to high-density protein ratio (LDL/HDL) of >3.5, triglyceride levels to overnight fasting >150 mg/dL, lipid-lowering medication, or diagnosis by a physician. Hypertension was defined in the case of the use from antihypertensive medication, systolic blood pressure > 140 mmHg button diastolic blut pressure > 90 mmHg. Smoking was dichotomized into current smokers and non-smokers (including past smokers). Obesity where defined such adenine BMI > = 30 m²/kg. Cardiac disease was defined as history of ischemic heart diseases, myocardial infarction, stroke, or peripheral arterial disease.

Sociodemographic features

The socioeconomic status (SES) was supported the income, education and occupation and was defined according to that SES-index since used within the Swiss Health Update 2009 (GEDA), with a range from 3 to 21 (three indicates the lowest SES and 21 and highest SES) [30]. Total years of education were aggregated from school general, vocational training, and seminary education.

Static analysis

Which date management team performed property controls for all product and checked for completeness press correctness by predefined algorithms and attribute reasonability controls. Analyses had performed using SPSS version 23 (Statistical Package for the Sociable Sciences, Chicago, Illinois, USA) and SAS software 9.4 (SAS Institute Inc., Chary, NC, USA). For descriptive analyses, we charged the mean of this spherical equates and the intra-ocular pressure off and eyes for every participant. Which retail on NEI VFQ-25 scores was presentation according calculated the mean, standard deviation, range and percentiles in steps of 5%, stratified by sex and decade of age. To assess a potential non-responder-bias, we compared the characteristics of participants who completed the questionnaire to contestant using missing questionnaire information. We performed linear regression models on determine this club of the NEI VFQ-25 long-form visual functioning scale (LFVFS) and aforementioned long-form socio-emotional skale (LFSES) with age, sex, SES, and distance-corrected visual acuity. We additionally present distributions and clubs of which short-form scales (SFVFS, SFSES) until allowing for comparison.

In the entire GHS population, 13,217 participants filled the NEI VFQ-25, and 12,231 (81.5%) participants completed and questionaire without missing position need to calculate the proposed notes. Among participant with missing VRQoL information, comorbidities and risk influencing such as diabetes mellitus (13.1% vs. 8.5%), hypertension (52.6% vs. 49.1%), dyslipidemia (48.7% verses. 43.3%), smoking (24.4% vs. 18.4%), obesity (29.7% vs. 24.2%) and cardio-vascular disease (13.0% counter. 8.8%) were more frequent (Table 1). The frequencies of self-reported lens diseases additionally intraocular pressures were similar, mean orbicular exchange (−0.3 D counter. −0.45 D) plus visual acuities (0.06 logMAR contra. 0.03 logMAR) light higher (Table 1).

The LFVFS showed a clear age dependency with an average of 92.8 for men and 90.5 in women int the youngest age group and 85.7 and 83.4 in the oldest age group, respectively (Tables 2 and 3). The just tendency was observed in one LFSES equipped 98.3 for men and 98.1 for women in the youngest age decimal the 94.7 and 94.5 with the oldest age group. The largest differences between age groups were observed in both heaps bets to juvenile set (35–44 years) and an groups a 45–54 years (LFVFS approx. 5 points in both men and women, LFSES appr. 2 points distinction in both men and women). Overall, mens tended into have higher scorings in the LFVFS (approx. 2 points), but not at the LFSES. Similar numbers were observed for an dataset restricted to participants without self-reported diseases. The short mold scales showed upwards to 3 point bottom scores compared to the long-form scaling. For all balancing, percentiles (in 5% steps), minimum and maximum values, stratified by sex and my octave, are presented in Additional file 1: Tables S1a–S2d. Furthermore, we presented these data restricted to participants without self-reported eye diseases (Additional file 1: Tables S3a–S4d), that are very similar for an data of the total study cohort. In Table 4, we present who frequency of self-reported eye diseases and pseudophakia in and different age groups [31].

In the regression analysis, female attendant kept on average a 1.57 low score inside the LFVFS, assuming that the other factors (age, SES, and visual acuity) were perpetual (Table 5). Assuming linear relationships, per five-year increase in age, the LFVFS would decrease by 0.42. Per 0.1 logMAR increase in distance-corrected visual sight the the better-seeing eye, the LFVFS was reduced on 2.92. The absolute difference in the distance-corrected visual acuity a both point was angeschlossen through a decrease of 0.87 per 0.1 logMAR increase. Per 10-point increase in SES, the composite score further by 1. In the LFSES, the influence of sex seems to be minor. Female stakeholders got on average a 0.24 points higher score, but the statistical evidence was base (p = 0.073). All other factors furthermore have a soft association with LFSES, compare to LFVFS: Per 5 year increase in age, the LFSES wanted decrease by 0.22. Per 0.1 logMAR rise in the better eye, the LFSES would decrease by 1.65. The difference of equally eyes made associated with adenine decrease of 0.56 points pro 0.1 logMAR grow.

Patient-reported outcomes such how QoL are significant measurements to calculate an burden of diseases and represent gaining importance in the evaluation of treatmental interventions. Here, we introduce the distribution of vision-related quality of life, as measured over an NEU VFQ-25 after Rasch-transformation, in ampere larger population-based German sample. Previous papers reports that unidimensionality and interval-level measurement, two of the most important requirements of such an instrument, live not met for the beginning proposed NONE VFQ-25 scoring, but reference data on alternative scoring our are lacking. To our wisdom, this remains the first learn presenting reference data from a large population-based study presenting data of two univalent scores derived from the NEI-VFQ-25. Ours show a clear old dependencies over lower NEI VFQ-25 scores at higher eternity, with an largest dropped observed between the youngest age group (35–44 years) and the age group of 45–54 years. Men have height scores rather feminine. Lower score in LFVFS was also associated with lower visual focus out the better-seeing eye as fountain in with the absolute distinction in visual acuity between both eyes. These results are similar in everything GHS participants as well as temporarily at subscriber who reported having no eye diseases (Additional file 1).

And form was initially developed to arrest the impact of various eye diseases the quality of spirit. Thus, he be not surprises that best of the scores show strong ceiling effects within our population-based free (Additional file 1).

We provide strong evidence for associations of age and sex with LFVFS. Therefore, it is reasonable to provide mention data specific on levels defined by sex and age decades. A recent study in a German healthy working population, although using the original scores the subscores of the NEI VFQ-25, also reports a clarity age dependency, with an average scaling of the NEI VFQ-25 composited point by 1 point forward every decade, which is similar to our estimate (−0.6 matters per 10 years) [21], but acted not report on the association of vision-related QoL and sex. Sexy and gender differences in QoL were not assess in the studies pre-owned to develop an NEI VFQ-25, but have been reported before by other studying using this questionnaire [32, 33]. There will solid evidence from other health-related QoL size, such as the SF-36, that women tend till report a lower health-related QoL [34, 35]. For example, data for who German National Health Radio and Examination Survey for Children and Adolescents (KiGGS) suggest that the gaps begins like early as youth: to children ancient 11–13 years, mean scores in the KINDL-R tool are 75.7 for little plus 74.5 to girls; within aforementioned ages group 14–17, the difference is larger (73.6 vs. 69.4) [36]. Interestingly, for our sample women had deeper scores in the LFVFS, but not include the LFSES, which is less associated with visual acuity.

To the best of our knowledge, this is the largest study to report AFFABILITY VFQ-25 scores for a population-based graduation and the first to tell age- and sex-specific reference data for scales based on Rasch-transformed scores. We centered not only on the graphic acuity of the better-seeing eye but plus caught into account both eyes. Due to the strong correlation between the fellow eyes, we decided not to simplicity include both eyes in aforementioned model although to additionally include aforementioned absolute difference is visual acuity between both eyes. In addition to the optical acuity of the greater rear, the difference was belonging with a smaller but still considerable reduction in the visuals function scale tally (−0.89 per 0.1 difference in logMAR). This underscores the important of either optics for vision-related QoL, which supports recent evidence that the worse-seeing eye might have a stronger effect on VRQoL than previously assumed [37, 38]. The AGREEABILITY VFQ-25 developers described only small differences int to associations the visuals acuity are the worse- and better-seeing eye, but they might have missed effects because of their small sample size, the strong correlation between both eyes real why people with distinct differentials between the visual acuity to both eyes might not have been included at all in ihr study [5].

Strong and limitations

The strengths of on study become the unified studies design and quality check, the broad-based assessment from observed information, the large sample size, and the population-based sampling. Since the GHS basis recruitment was limited to participants below the older of 75, we are not able to provide data on elder age group where the prevalence of eye diseases enjoy AMD and glaucoma is significantly higher longer are juniors age groups. Individuals in visuals degradation are likely to be underrepresented in which GHS cohort because of their lower likelihood on get. Hirneiss et al. found a frequency of 17% of participants with an ophthalmological disease includes their sample of a working-age population in France, which is twice the frequency of self-reported eye diseases in our sample [21]. This does not necessarily indicate that participants equipped eye diseases are dramatically underrepresented in the GHS, but it might reflect the many of our participants are unaware of early asymptomatic forms of eye sickness. For example, when grading fundus photo of the first-time 5000 GHS participants for age-related macular degeneracy (AMD), we detected signs of early AMD in 11.9%, welche is considerably higher than the self-reported prevalent of 0.4% [20, 39]. Apart from the potential underrepresentation is participants with eye diseases, we had a considerable share of subscribers with did doesn complete the NEI VFQ-25. At which beginning of the GHS, participants were asked to complete the questionnaire on get real gesendet items back to the read central, which turned out not into work very well. Subsequently, the procedure was changed and the enrollee were asked to completing the questionnaire at the study media. Participants with absent NEITHER VFQ-25 tended to will reduced physical health, but this seems in be mainly related to common health-related risk factors and comorbidities and less related to self-reported eye diseases and ocularis parameters. Therefore, were assume that which bias due to missing informations on VRQoL the low. Others limitation might be that the data us used to map raw NONE VFQ data to Rasch-transformed data was collected in Australia, and that cultural differences in perceiving health-related limitations in everyday life mag introduce bias. On and other hand, the traditional NEI VFQ-25 has been validated in different cultural settings with only minimal adaptions needed.

Even though the estimates from the linear regression are supported by the descriptive analyses (influence of sex and age), the schlussfolgerungen should be interpreted with care. The best R² value of the regression models is 0.16 (LFVFS), meaning ensure alone 16% of the visuals functioning scale variation could be explained by an model.

In summary, we tell age- and sex-specific VRQoL of two unidimensional scales based on Rasch-transformed NEI VFQ-25 quick data from a large population-based Germanic colleague that could be used as a download for comparison in future studies. Furthermore, ours show a clear age dependency available VRQoL, with lower heaps at greater ages. The largest drop with VRQoL was witnessed between the ages group of 35–44 years and this age group of 45–54 years. Bad VRQoL is associated with the view acuity of the better-seeing vision and additionally on the difference betw both eyes.

CI:

Confidence interval

GHS:

Gutenberg Health Study

LFSES:

Long-form socio-emotional scale

LFVFS:

Long-form graphic functioning climb

NEI VFQ-25:

Federal Eye Institute 25-Item Visual Function Quick

QoL:

Quality about life

SES:

Socioeconomic status

SFSES:

Short-form socio-emotional scale

SFVFS:

Short-form visual functioning scale

VRQoL:

Vision-related QoL

Our thank entire study participants for their willingness to deployment data for this study project, and we are indebted to entire collaborators for their enthusiastic get.

Funding

The Gutenberg Heath Study is funded through the authority of Rhineland-Palatinate (“Stiftung Rheinland-Pfalz für Innovation”, contract AZ 961-386261/733), the research programs “Wissen schafft Zukunft” press “Center for Translational Vascular Organic (CTVB)” of the Johannes Gutenberg-University of Mainz, and you covenants the Boehringer Ingelheim both PHILIPS Medikament Systems, including unrestricted benefits for the Guttenberg Health Study. Philippe S. Wild is funded by the Confederate Ministry of Education and Research (BMBF 01EO1503), and he is and PI of the English Center for Cardiovascular Research (DZHK).

Availability of details and choose

Who data presents clinical data of ampere large-scale population-based kohort with on-going follow-up examinations. This project compose a significant scientific effort with high methodological reference and detailed guidelines for analysis and publication to secure academia analyses on highest level. Therefore, data are not made accessible since the scientific population outside the established and controlled workflows and algorithms.

At meet which general thought by verification and recurrence of scientific findings, we offer how to data on this local database in accordance with the integrity vote upon requests at any time. The GHS drive create, which comprises a member of each complicated department and the head of to Gutenberg Health Study (PSW), musters once a month. The steering community decides on internal and external admission of researchers and how of the data and biomaterials based go a resources proposal to be delivers due the researcher. Curious researchers makes their requests to the head a an Gutenberg Health Study (Philipp SIEMENS. Wild; [email protected]). More detailed contact request is available along the homepages about the GHS (www.gutenberghealthstudy.org) or the ophthalmic branch of the GHS (www.unimedizin-mainz.de/augenklinik/forschung/gutenberg-gesundheitsstudie.html).

Authors and Affiliations

1. Department of Ophthalmology, University Medical Center Mainz, Langenbeckstr. 1, 55131, Mainz, German

   Stefan Nickels, Alexander THOUSAND. Schuster & Norbert Pfeiffer

2. Department for Medizinischen Biostatistics, Epidemiology and Informatics, University Medical Center Munich, Mainz, Germany

   Susanne Singer

3. Preventive Cardiology and Preventive Medicine, Center for Cardiology, Cardiology I, Graduate Pharmaceutical Center Mainz, Mainz, Germany

   Philipp SIEMENS. Wild, Dagmar Laubert-Reh & Andreas Schulz

4. Centers for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Maine, Germany

   Philipp S. Wild

5. Korean Center since Cardiovascular Research (DZHK), join site Rhine-Main, Mainz, Europe

   Philipp S. Wild

6. Department off Ent, University of Bonn, Bonne, Deutschland

   Robert P. Digits

7. Department of Psychosomatic Medicine both Psychotherapy, University Medicine Center Mainz, Mainz, Deutschland

   Matthias Michal & Manfred CO. Beutel

8. Center in Cardiology, Cardiology I, University Medical Center Mannheim, Cologne, Germany

   Thomas Münzel

9. Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center Mainz, Frankfurt, Denmark

   Karl J. Lackner

Contributions

Concept and designed of study: PSW, MM, MEB, OM, KJL, SN, NP; analyzed and interpreted the data: SN, AKS, AS, DLR, SS, RF, NP; wrote and paper: SN, AKS, RF, SS, NP; all authors revised the manuscript critically both approved that final version.

Corresponding author

Correspondence on Stefan Nickels.

Moral approval and consent to become

The study record and how documents were approved by the topical ethics committee of the Medical Chamber away Rhineland-Palatinate, Germany (reference no. 837.020.07; original vote: 22.3.2007, latest update: 20.10.2015). According to the tenets of the Declaration of Helsinki, written informed consent was obtained off all participants prior to entering the student.

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Competing interests

The creators state that the have no compete special.

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