The population of persons aged 85 and older in the United States is expected to more than triple over the next forty years.1 With advanced age being one of the strongest predictors of nursing home placement, the number of nursing home residents in the United States is expected to more than quadruple in just the next twenty years.2 Vision impairment is a common problem among older adult nursing home residents. These residents are 3 to 30 times more likely to have vision impairment than community dwelling older adults.3-5 It has been demonstrated that refractive error correction and cataract surgery can improve visual function and vision-related quality of life, slow functional decline and reduce depressive symptoms among nursing home residents.6-8 However, the number of nursing home residents receiving eye examination is low, despite the high prevalence of vision impairment in this group and the existence of interventions proven to be effective in correcting vision impairment. One issue is that in the United States eye examinations are not federally mandated for nursing home residents,9 and research has suggested that less than 50% of residents ever receive an eye examination after placement.4,10-14

Legislation enacted in 1987 required the implementation of the National Resident Assessment Instrument (RAI) for all nursing homes participating in the federal health care programs Medicare and Medicaid. The RAI is comprised of two parts, the Minimum Data Set (MDS) and Resident Assessment Protocols (RAPs). The MDS is a nearly four hundred item multi-dimensional assessment intended to reflect the resident's status over the previous week. Residents are evaluated using the MDS on admission, quarterly, annually, and whenever there is a significant change in status.15 The MDS is completed by each facility's designated RAI/MDS nurse coordinator and ideally incorporates input from multiple sources, including the resident and other healthcare providers in the nursing home. The MDS assessment together with the triggered RAP (in the case of impairment on the MDS assessment) is intended to guide nursing home staff to the appropriate care that a resident would need.16 In the case of vision this may mean arranging for professional vision examination or making vision-related environmental or care modifications. The currently administered version (namely MDS 2.0) has a section collectively referred to as “Vision Patterns,” which assesses three areas (seeTable 1): 1) quality of vision, 2) visual limitations/difficulties, and 3) use of visual appliances. For this system to function as intended, the MDS must be a valid screening assessment of the visual status of residents. A previous investigation of the validity of the Vision Patterns section of the MDS found that it had questionable validity as a mechanism for triggering comprehensive eye examinations for nursing home residents who have vision impairment.17

Certified nursing assistants (CNA) provide the bulk of direct care to nursing home residents in the United States. Their duties include assisting with activities of daily living such as feeding, bathing, and toileting, as well as monitoring weight and vital signs such as temperature. In essence, they spend considerable one-on-one time observing and interacting with residents. CNA's training typically consists of a 10 to 12 week didactic program that includes supervised clinical experiences. Given the close direct working relationship CNAs have with residents, one might expect that they would be very familiar with residents’ everyday visual function and with the extent to which they are experiencing difficulties. Governmental guidelines for completing the MDS suggest that the MDS nurse coordinator solicit the CNA's input. The extent to which CNAs participate in formulating the MDS vision assessment is unknown. One previous study reported that CNAs are not regularly a part of the care plan team18 while another found that, in the absence of resident selfreports by the resident for MDS items, CNAs assessments were solicited.19 A question that remains unanswered is to what extent CNAs’ judgments about residents’ vision-targeted quality of life (e.g., visual difficulties) agrees with the MDS rating provided by the nurse coordinator. The purpose of this study was to examine the relationship between the nurse-coordinator-charted MDS 2.0 assessment of Vision Patterns and the CNA rated Nursing Home Vision-Targeted Health-Related Quality of Life Questionnaire (NHVQoL).

The mean age of subjects was 81 years (SD 8.2) with a range going from 60 to 102 (Table 2). Approximately 75% of participants were white, and 81% of the sample were women. Most participants had been residents for at least 1 year with a mean length of stay of 1.9 years (SD 2.0) and a range covering from 0.1 to 12.4 years. Mean MMSE score was 20.9 (SD 4.7). MMSE scores below 24, typically used as a cutoff point for cognitive impairment indicative of dementia, were seen in 66% (247 of 371) of subjects. Participants had a mean of 5.6 chronic medical conditions (ranging from 0 to 15). The MDS rating for quality of vision ranged from 0 to 4 (see Table 1 for the descriptor associated with each category). The majority of residents (59%) were rated as having “adequate” vision, with 29% rated as having “impaired” vision and 9% with “moderately impaired” vision. Together, “highly” and “severely impaired” vision represented about 2% of the sample.

Mean distance acuity in each participant's better eye was 0.43 logMAR with a range going from -0.06 to 1.1 logMAR. Distance acuity in the worse eye ranged from 0.02 to 1.2 log-MAR. Using the United States definition of statutory blindness (20/200 or less in the better eye), 6.2% of subjects were legally blind. Distance acuity in the better eye worse than 20/40 (Snellen chart) is a frequently used criterion in the United States for defining visual impairment. Using this criterion 211 of 369 subjects (57.1%) were visually impaired. Mean near acuity in the better eye was 0.57 logMAR with a range going from -0.04 to 1.4 logMAR. Mean near acuity in the worse eye was 0.81 logMAR ranging from 0 to 1.4 logMAR.

Regarding the scores on each of the NHVQoL subscales, as the MDS rating indicated worse visual function, the corresponding mean NHVQoL score decreased (Table 3). At the Adequate and Impaired MDS levels, all mean NHVQoL scores were in the 90s except for the “General Vision”. subscale. Several mean scores of those participants belonging to the Moderately-impaired category are also in the 90s with a few in the 80s and one in the 70s (General Vision). In the combined Severely/Highly-impaired category, NHVQoL scores are appreciably lower.

No significant differences were seen in NHVQoL scores when comparing those with “Adequate” MDS vision rating and “Mild Impaired” for the subscales of Ocular Symptoms, Activities of Daily Living, Mobility, Psychological Stress and Adaptation/Coping. Only the NHVQoL subscale scores for Psychological Stress and General Vision showed statistically significant differences between those in the “Mild” and “Moderate” impairment categories. All subscale scores of the NHVQoL, except for Ocular Symptoms, were statistically significant between “Moderate” and “Highly” impaired MDS levels. When comparing a two-step change in the MDS; e.g. from the “Adequate” to the “Moderately impaired” category, most NHVQoL scores (except those for ADL and Adaptation/Coping) were statistically significant. When looking at the extremes of the MDS vision rating scale; i.e., comparing “Adequate” vision and “Highly impaired” vision, all subscale scores were significantly different between the two rating groups, including Ocular Symptoms.

Correlations between all acuity measures and the NHVQoL subscale scores were statistically significant (all P<0.025) except for that between the ocular symptoms subscale and worse eye's distance and near acuity (seeTable 4). All correlation coefficients between logMAR visual acuity measures and NHVQoL scores were negative, indicating that better acuity (lower logMAR scores) was associated with higher NHVQoL scores. The highest correlations were found between both distance and near acuity measures and the Reading subscale score.

Our results show that as a nursing home resident's vision is rated as more impaired by the nurse coordinator on the MDS, the CNA's judgment of vision-targeted health-related quality of life is also likely to produce lower scores. Thus, there appears to be a general agreement between the MDS ratings as provided by the nurse coordinator/care team and the CNA's ratings of vision-targeted quality of life. Only the NHVQoL's Ocular Symptom subscale turned out to be unrelated to MDS levels, regardless of which categories were compared. It is important to point out that while the CNA's scores on the NHVQoL were lower as the MDS ratings moved toward greater impairment levels, the decreases in scores across MDS categories ranging from Adequate to Moderately Impaired are modest, even though statistically significant, and in some cases there are no decreases, depending on the specific subscale under analysis. This suggests that from the CNA's perspective (based on extensive everyday observation and interaction with the resident), visual functional differences in residents placed in the first two to three MDS categories (adequate, impaired, moderately impaired) are not readily differentiated based on the everyday behavior of residents and/or their interactions with the CNA.

On the other hand, the CNA's assessment of vision-related quality of life is dramatically worse (e.g., 20 points lower) for those residents in the combined MDS category of highly/severely impaired, as compared to those in the moderate impairment category. The MDS descriptors for highly and severely impaired levels correspond to very serious vision impairment or no light perception. The step between moderate impairment and the combined highly/severely impaired category appears to be large enough to allow both the MDS nurse coordinator and the CNAs (as revealed on the NHVQoL) to distinguish between these groups. Thus, the CNAs seem to be readily aware of serious visual disabilities through caring for residents and interacting with them. In general, our results show that the CNAs’ responses on the NHVQoL have construct validity with respect to visual acuity, in that CNAs indicated that persons with worse visual acuity for near or distance vision had more difficulties in the visual activities of daily living including reading.

This is one of very few studies to evaluate CNAs’ assessments of the quality of life as related to the MDS and the first to specifically focus on their assessment as related to the MDS vision pattern section. Most studies directly relating CNAs’ assessments and the quality of nursing home care in the United States have concentrated on the effects of staffing and turnover.24 Higher levels of CNA staffing and increased direct CNA contact hours have been associated with some positive nursing home outcomes including reduced levels of hospitalization and lower levels of pressure sore development.25,26 In other studies CNAs have been able to assess the pain level of residents with some degree of accuracy compared to clinical assessment.27,28 One study has suggested that CNA pain assessment more closely matches analgesic use than does the MDS pain assessment.19 In the current study, there was also significant associations between CNAs estimate of vision-targeted quality of life and resident's visual acuity.

The strengths of this study include its large sample size recrited across a large number of nursing homes and the use of a validated and nursing home vision-specific quality of life measure. We do recognize that despite its large sample size, the number of residents with severely impaired vision was low. Additionally, this study evaluated the association of two proxy assessments of visual status by facility staff within nursing homes (i.e. MDS nurse coordinators and CNAs). Proxy assessment of health related quality of life has been shown to be subject to both over and under estimation bias28 with the NHVQoL not being specifically designed with proxy observer use in mind.

Overall, the results of this study suggest that MDS nurse coordinators and CNAs at the nursing homes participating in this study were in general good agreement as to the visual status of their residents as measured through the MDS Visual Patterns section and the NHVQoL respectively. This is a positive finding in that CNAs ratings of residents’ vision-targeted quality of life were correlated with residents’ objective visual acuities. Although it is unknown if CNAs at the participating nursing homes were a part of the care plan team, the results of this study provide evidence that CNAs assessments should be solicited for completion of the MDS Visual Patterns section. In the absence of a federal mandate in the U.S. for routine vision examination for nursing home residents by an optometrist or ophthalmologist, the MDS Vision Patterns evaluation is a key component in assuring that nursing home residents in the United States receive appropriate referral for eye care services. Incorporating CNA assessments as a part of this process may increase the number of residents who are appropriately referred for eye care services. However, it should be cautioned that while CNAs appear to be able to differentiate those residents with severe vision problems from those who do not have severe vision problems, the NHVQoL scores for those belonging to the MDS categories Adequate, Impaired, And Moderately Impaired were very similar. This may be attributable to a number of factors, including problems with how the MDS rating criteria are defined,30 the MDS nurse coordinators not experiencing enough close contact with each resident to understand their daily visual difficulties, inadequate validity of the MDS with visual acuity,17 or the CNA's inability to detect more subtle visual difficulties through the resident's behavior. Future research should be directed at clarifying the validity of the MDS and how it should be implemented if it is to be used to trigger eye care services for nursing home residents in the U.S.