The Effect of Implementing an Adapted Standardized Vision Screening Process on an Underserved Spanish Speaking Population of Children
Taylor Giambrone*1, Diego Chaves - Gnecco1, Jeffrey M. Rohay1, Carl Ross2, Susan A. Albrecht1
2Robert Morris University
*Corresponding author: Taylor Giambrone, School of Nursing, 3500 Victoria Street, Pittsburgh, PA 15213, University of Pittsburgh, USA. Tel:+17173687077; Email: email@example.com
Date: 07 May, 2018; Accepted Date: 18 June, 2018; Published
Date: 22 June, 2018
Giambrone T, Gnecco DC, Rohay JM, Ross C, Albrecht
SA (2018) The Effect of Implementing an Adapted Standardized Vision Screening
Process on an Underserved Spanish Speaking Population of Children. Int J Nurs
Res Health Care: IJNHR-110. DOI: 10.29011/ IJNHR-110. 100010.
The purpose of this research study was to assess the impact of the
implementation of a standardized vision screening processes in a particular
sample known to be prompt to barriers to health care access (e.g.: lower
socioeconomic status, lack of health insurance status and cultural and
communication barriers). Studies have determined that the lack of
standardization is a contributing factor to the low rate of screening in school
age children. A gap in knowledge exists within the needs of Spanish speaking children
and their families, due to the lack of standardization as well as the numerous
disparities facing this specific population.
new adapted standardized screening process was implemented at the Salud Para Niños
(Health for the Children) (SPN) program in Pittsburgh, PA. SPN provides
low-cost or free primary care and culturally competent community outreach to
Spanish speaking children and their families. The rate of completion of the
old, non- standardized screening tool (kindergarten chart), was compared to the
new standardized tool (LEA symbol chart). A hand chart was also used to address
any language barrier. Eighteen children between the ages of 5 - 17 were asked
to attempt both screenings in a randomized order. The primary outcome variable
in this study was the completion of the old examination process versus the new
Our results indicate that a standardized screening tool, such as the LEA symbol
chart, is effective at producing more reliable measurements in Spanish speaking
children. While the Center for Children’s Vision and Eye Health recognize this
chart as an evidence - based tool for English speaking children, these results
support the implementation of this tool to improve quality of vision screenings
in primary care settings for populations facing a language barrier.
Barrier; Pediatric; Primary Care; Underserved Populations; Vision Screening
Healthy People 2020 and the U.S. Preventative Task Force
have recognized vision screening for all youth as a significant public health
priority in the United States for many years . They have partnered with
numerous national agencies to implement standardized practice guidelines and
policies to address existing disparities to providing this vision care. Currently
in the United States, there are no national standards for vision screenings. Each
state respectively has the power to determine the practice guidelines
implemented within schools and physician offices. Due to the inconsistency
between states, as well as the lack of standardization and evidence - based
screening processes, a gap in preventative care exists. Studies have determined
that the current low rate of preschool vision screening in primary care
practices may be attributed to inconsistent screening recommendations and
insufficient implementation of selected tests .
This problem is particularly evident in children and adolescents of low socioeconomic
status and those with a language barrier. Therefore, it is important to
recognize the need for equitable care for all children as it relates to vision
screening to increase their psychosocial well-being and give them optimal
opportunities for success.
A 2011 National Survey of Children’s Health conducted by the Data Resource Center for Child and Adolescent Health (DRC) found that only 58% of children who were below the federal poverty level were screened for visual deficits at least once before the age of 17. Those that were uninsured at the time of the survey also demonstrated a lower screening rate of 58%, and of Hispanic children whose primary household language was Spanish, 48% had only been screened once before the age of 17 . These statistics depict the disparities that exist in equitable care across all populations and highlight the need to address common barriers within underserved populations. The United States Preventive Services Task Force (USPSTF) recommends instrument-based vision screening for all children at least once between the ages of 3 and 5 years . Another study conducted by Hered & Rothstein found that fewer than 25% of U.S. preschool children had undergone vision screenings by either private or government programs . They attribute this statistic to inconsistent screening recommendations, insufficient guidance on implementation of tests, and several frequent patient barriers that effect the integration of screening tools in primary care settings.
Vision screenings are used to determine the need for a person to follow up with an ophthalmologist for a comprehensive eye exam, where they are further assessed for a variety of conditions. Therefore, a child should obtain a vision screening on a regular basis either at school or in a primary care setting at least once a year  identify vision problems early on and begin the referral process. Over 20% of school-age children have some form of an ocular conditions. The World Health Organization (WHO) estimates that 7 million children between the ages of five and 15 years old are affected by non-refractive disease, meaning that it is linked to a disease process more complex than just near or farsightedness . Access to regular vision screenings can find that the child may need a more comprehensive exam to prevent long term effects. A study funded by the National Eye Institute (NEI), part of the National Institutes of Health found, “that uncorrected farsightedness (hyperopia) in preschool children is associated with significantly worse performance on a test of early literacy” . Long term effects of lack of optimal standardized vision screenings can lead to decreased psychosocial well-being of a child or adolescent. “One of the challenges to the investigation of a causal relationship between vision and literacy is the potential confounding effect of socioeconomic factors. It is well known that socioeconomic deprivation is associated with poor levels of literacy” . Therefore, it is still of equal importance to ensure that all children of every background are given the same opportunity to achieve in school. A 2016 study entitled “Parent, Teacher, and Student Perspectives on How Corrective Lenses Improve Child Wellbeing and School Function” found that stress and poor school performance are two of the most prevalent experiences related to vision problems by children of all ages and their families .
A search of the database PUBMED offered numerous results
supporting the need for improvement in pediatric vision screenings, especially
in primary care centers. Because there is no national standard for pediatric
vision screening, many studies analyzed the number of practices that do and do
not adhere to the American Academy of Pediatrics (AAP) recommended guidelines. Most
recent policy recommendation by the AAP, AAPO, AAPOS and AACO released in 2016,
stressed the importance of early screening and detection of vision problems in
children, as a child will not typically voice problems with their vision. Included
in this report was a table of guidelines for screening children and
adolescents, attempting to standardize the process and provide guidelines for
implementation, but lacking insight on minority populations . In 2006,
Kemper & Clark conducted a study on preschool vision screening in pediatric
practices, with the objective of identifying the barriers to this process and
the impact of new technology and economic incentives on practice. The study
identified the three broad categories related to barriers in vision screenings
as practice related, test related, and referral related . To determine the
efficacy of pediatric vision screenings in primary care practice, Hered and
Wood’s 2013 study concluded that over half of the patients referred for further
ophthalmologic examination after failing initial testing did not follow-up. This
was especially apparent in patients from minority populations and low-income
families . The results of these studies are all encompassing of the
hundreds of similar studies reporting the same problems with the pediatric
vision screenings in the United States.
A 2016 study published in the British Journal of Ophthalmology stated, “A number of studies have described an association between lower socioeconomic status and the incidence of pediatric eye conditions including refractive error, strabismus, and amblyopia” . Therefore, a need exists for the availability of affordable preventative health care to be provided for this specific patient population. While a large portion of existing studies focus on early screening and barriers related to low socioeconomic backgrounds, a gap in knowledge exists within the needs of specific ethnic groups. This necessitates a more thorough examination on how a standardized process can be implemented in an adapted manner to address all the needs of a specific patient population. According to the 2010 U.S. Census, approximately 30,000 Hispanics or Latinos live in Southwestern Pennsylvania and one third of them are under the age of 18 years . A large portion of this population will face economic hardships due to language barriers, citizenship status, and acculturation. When considering the large proportion of Spanish speaking children in need of preventative health care in western Pennsylvania, the focus will not only include early screening and common barriers, but the reality that most of these children and adolescents will be receiving their first vision screening.
In order to address the very evident health disparities
plaguing underserved populations, specifically in Pittsburgh, PA, Dr. Diego
Chaves-Gnecco established Salud (Students, residents, faculty and Latinos
United against health Disparities) Para Niños (Health for the Children). An
Agency for Healthcare Research and Quality (AHRQ) innovations exchange article
describes SPN as a program that provides low-cost (sometimes free) primary care
and culturally competent community outreach to Spanish and Portuguese speaking
children and their families in southwestern PA. The care provided by this
clinic is essential to the community and is the first of its kind in this area .
SPN is a free clinic program makes use of existing clinical space and depends
on donated resources and volunteers; therefore, it is faced with even more
obstacles when trying to implement changes in practice. With respect to vision
screenings, the staff does try to screen every eligible child; however, a more
reliable and consistent screening process could be introduced to provide better
patient care to this population. SPN’s vision screening program is predictably
not standardized and is even less effective because of the innumerous
socioeconomic barriers the patient population face in terms of accessing
quality healthcare. By implementing an adapted standardized vision screening
process, and doing so in a cost-effective and sustainable manner, the clinic will
be getting closer to providing the most optimal care possible.
To address the lack of national standard and variation of screenings completed throughout various healthcare settings, a standardized process was implemented at SPN. It followed the recommendations presented by the National Center for Children’s Vision & Eye Health which follows AAP guidelines, and was further adapted for Spanish speaking children and their families . After much observation, research, and collaboration at the clinic, a sustainable and effective process was established with clinic coordinators. This study presents the results of implementing a standardized process into practice and the effect on patient care. The standardized process recommended by the AAP was adapted with permission to fit this specific patient population.
Patients from the clinic were included in the study if they spoke Spanish primarily at home and were between the ages of five and seventeen. To gain a more well-rounded understanding of the differences in screening, the minimum age of five was determined to be optimal for this study. Selection for participation of subjects five years or older allowed for increased opportunity for cooperation with the screening. A study entitled Preschool Vision Screening in Pediatric Practices noted, “the children’s (ages 3 & 4) lack of cooperation with testing was the major barrier (49%)” . Screening younger children is more time consuming and more challenging. While this is an important aspect to address, this study is intended to provide a method for screening focused on language barriers rather than age. The goal number of participants was 20 children who spoke Spanish as their primary language at home and required that the vision screening process be completed in Spanish.
Informed consent documents were provided in Spanish containing information regarding the intent, procedures, and risks and benefits of the study. It clearly stated that participation was completely voluntary and provided contact information for the investigators if needed. The old non-standardized chart (Table 1) used for the vision screenings was the kindergarten chart, made up of various symbols, a large majority not easily identifiable by a young child. For example, this chart contains a sailboat, a cross, a flag, and a teacup. This chart is not recommended by any national agency as it does not accurately measure visual acuity because the symbols are not easily identifiable nor precisely printed to scale as they should be. The charts’ history and developer are unknown. Unfortunately, it is still commonly utilized in many healthcare settings as it was one of the first types of pediatric screening tools to be made available .
The new standardized chart (Table 2) is the LEA symbol chart which “contain[s] large examples of a house, apple, circle, and square” . These symbols are more easily identifiable by a child and are culturally neutral. Meaning that one child may identify the symbol as a circle, while another may call it a ball. Both are correct, thereby considering the various answers many children provide who have not had formal schooling yet. The LEA symbol chart also comes with a smaller hand chart that is comprised of one row of the symbols that can be used initially to familiarize the child with the symbols and determine how they identify them. This small hand chart can also be held by the child and they can point to and identify the appropriate symbol that is being referenced from the wall chart if they are shy or cannot communicate appropriately. This can be especially beneficial in settings where a translator is not available, and a language barrier is present, since the vision screening can essentially be done using limited communication. Formal eye occluders were utilized to cover each eye for the exam. The use of an eye occluder or eye patch as recommended by the AAP is essential to obtaining accurate and reliable screening measurements .
This is an experimental descriptive study that was implemented using a randomized crossover methodological design. Each participant completed the old vision screening process as part of their clinic visit, as well as the newly adapted standardized process. The order in which the screenings were completed was randomized using a permuted block design. Data collected included whether the child completed the screening (yes or no) and the time it took to do so. The child’s age and gender were also noted as secondary variables. For the purpose of this study, all subjects had to attempt completion of the screening processes using the kindergarten chart and the LEA symbol chart. Completion of the screening is determined by the child’s ability to identify the objects due to visual acuity rather than their inability to understand the chart itself. Typically, if a Spanish speaking child can read or identify letters appropriately, they may be screened using the Snellen chart. The Snellen chart is the most common tool used throughout the United States to measure visual acuity. However, the Snellen chart also does not meet the international guidelines for appropriate optotype distance and are not all standardized. With the goal of the study being to adapt a standardized process to a Spanish speaking population, it is more effectively done with a culturally neutral chart such as the LEA symbol . There is no way to adjust communication methods using the Snellen chart if required due to a language barrier. The study added an additional five minutes to the visit.
Nursing students from a large urban research-intensive university with a baccalaureate nursing program completed the screenings. Upon clinic arrival, the nursing students collected patient information including age, gender, and preferred language for communication. The students then completed an initial health assessment including collecting vital signs, height, weight, and vision screening given their respective age. At this point, it was determined whether the child does meet the inclusion criteria for the study. If inclusion criteria were met, verbal consent and assent was obtained from the guardian and child respectively after reviewing the consent form in Spanish. This was completed by the principle investigator and a third-party translator to ensure no undue influence occurred. Once this was completed, the child was randomly assigned to either group AB or BA, determining the order in which the vision screenings will the completed. Group AB received the old screening first then the new screening, conversely Group BA received the new screening first and then the old screening. The nursing students were familiarized with the correct administration of the new screening process as it was outlined in a document that was kept on site at all times. The children were then taught how to use the eye occluders by demonstration. If not capable of holding the eye occluder in place, another nursing student was available to hold it over the respective eye throughout the examination.
The old vision screening process had the child standing 20 feet away from the wall chart. While this is not incorrect for the Snellen and kindergarten chart, it is not the guideline for any other optotype screening chart . Having the child stand that far away in the small clinic space also lead to additional distractions and interruptions during the screening process causing additional stress. By moving the screening to 10 feet away, as recommended by the AAP, distractions and interruptions were decreased and it was much easier to communicate with the child in a noisy setting. The child was then instructed to cover the right eye first and once screening began the timer was started. The timer was not stopped when switching between eyes. The standard procedure is to have the child begin identifying the objects from the top line and move down. For the child to continue moving down the chart, they must get 50% of the line correct. The last line in which they achieve 50% correct is the final measurement. This process was repeated for the left eye.
The main difference between the old screening and the new
screening is that the child is to identify the symbols preemptively using the
hand chart provided to address any language barrier. Only the measurement from
the old screening process was recorded in the medical record since it is
necessary to first prove a positive change in practice prior to instituting a
change in charted measurements. The specific measurements of the new screening
process were not recorded as part of the data collection because it was not
relevant to the specific aims of the outcome variables. The procedure involves
minimal risk to the subject as the probability of harm/discomfort anticipated
in the new adapted standardized process is no greater than those encountered
during the administration of the old vision screening process. The only
identified risk factor is that the parent or child may become anxious due to
the increased time of screening and unfamiliarity with the tool.
The primary outcome variable in this study was the completion of the old examination process versus the new examination process. Time to complete the examination, if applicable, was also measured and analyzed to determine clinical efficiency. Secondary variables that were analyzed included age, gender, and order effect. A McNemar’s test, with a significance level of 0.05 was used for the stratified analysis of the primary variable due to the paired nominal data collected. Additional statistical measures such as Fisher’s exact and paired t-test were calculated with a significance level of 0.05, to determine possible order, age, or gender effect on the outcome due to the smaller sample size .
Initial frequency data was calculated for the variables. A total of 18 participants made up the study sample, which is a sufficient number for the feasibility of a pilot study implemented in a single location . The sample consisted of 6 (33.3%) females and 12 males (66.6%). The mean age of the participants was 10. 8 (± 4), with a range of exactly 5 to 17. For stratified analysis, the participants were divided into two age groups, ≤10 for elementary age and >10 for middle and high school. Seven participants (39%) fell into the younger age group, while 11 participants (62%) were in the older group. For chart A (the old screening tool) 8 participants could complete the screening (44%), while 10 participants could not complete the chart. All participants could complete chart B. Of those who completed the chart, the average time it took to complete chart A was 141.8 seconds (2 minutes and 21 seconds) ± 45.7 seconds. The range of time for chart A was 99 to 240 seconds (1 minute and 39 seconds to 4 minutes). The average time to complete chart B by all participants was 100. 7 seconds (1 minute and 40 seconds) ± 33.8 seconds. The range of time was 50 to 172 seconds (50 seconds to 2 minutes and 52 seconds). The screenings were completed in AB order by 11 participants, and BA order by 7 participants.
The primary variable of completion of the old non - standardized examination process versus the new adapted standardized process was found to have a significant 2-sided p-value of 0.002 using the McNemar’s test. This is demonstrative of the difference between the effective screening capabilities of the two charts. The amount of time it took participants to complete the two charts was statistically significantly different, with a p-value of 0.01. Meaning that the participants completed the vision screening process in less time utilizing the standardized chart compared to the non-standardized chart.
The secondary variables were analyzed for possible effects on the outcomes variables. Because every participant completed chart B, no secondary variable effect could be calculated related to the standardized screening tool. Therefore, the effect of secondary variables was only assessed on the data for chart A. For the non - standardized chart, four females and six males were unable to complete the chart, while two females and six males did complete the screening. A Fisher’s exact p-value of 0.638 was calculated, determining that there was no association between gender and the ability of the participant to complete the vision screening process utilizing the old chart.
Age affect was explored for chart A by dividing the participants into the age groups listed above. For those ≤ 10 years of age, six of the eight participants in this group could not complete chart A, which generated a p-value of 0.031 using a McNemar’s test. For the older participant group (> 10 years of age), a p-value of 0.125 was observed, with four of the ten participants within this group not completing chart. Overall, age effect was present with a significance of 0.02 for the old chart. This is significant in that the younger participants found it much more difficult to successfully be screened using the old chart.
Order effect was also a measure of interest, determining
whether the order in which they completed the different screenings had an
impact on the primary outcome variable. For chart A, eleven participants
completed the screenings in AB order, while the remaining seven were in the BA
category. A 2-sided p-value of 0.066 was calculated, approaching statistical
significance, in that a higher proportion of the participants that completed
chart B first could then could not go on to complete chart A. However, for the
participants who completed chart A first, the majority could go on to then
complete chart B. This could be attributed to the higher difficulty level of
the old screening tool in comparison to the new screening tool.
Our results indicate that a standardized screening tool, such as the LEA symbol chart, is effective at producing more reliable measurements in Spanish speaking children in a shorter period of time. Statistical analysis showed the LEA symbol chart produced results that are consistent with the findings of the numerous studies discussed previously in English speaking children, and why it is recommended by the AAP and supported by the National Center for Children’s Vision and Eye Health [4,14]. Additionally, these findings are consistent with previous studies on the efficacy of the LEA symbol chart in pediatric populations. Research has shown that the LEA chart is especially useful in the youngest of populations due to its simplicity, therefore leading to its ease of use in this specific patient population . Although this is not a nationally recognized guideline, our results support the idea that this tool can improve quality of vision screenings in primary care settings. Our results emphasize that standardized screenings’ overall efficacy may help to create a change in practice by re-enforcing the positive outcomes that proper screening can bring to a young child physically and psychosocially.
The adapted aspect of this new process that differs from any studies previously completed comes into importance with the specific patient population studied and the environment of SPN. The hand chart offers the ability to conduct the screening in a match method rather than verbally . This is beneficial in the presence of a language barriers and was utilized in this specific way for this study, which proved to help with the completion rate of chart B. While this is less frequently used among English speaking children, every single Spanish speaking participant in this study used this to establish a baseline identity of the objects. By identifying the objects first, potential misunderstanding is reduced between the nursing student and the patient given the language barrier . This procedure proved to very effective for the overall fluidity of the screening itself as well as the flow of patients through the clinic.
In a community clinic such as SPN free clinic, demand for care is always very high while resources typically fall short. While health care providers never want their care to be rushed, an important factor related to being able to provide effective care for the large number of those in need is time. The fluidity of the clinic and how effectively it cares for patients plays a large role in the healthcare provided. Therefore, it is important to note that it took less time for the participants in the study to complete the standardized chart (LEA symbol) compared to the non-standardized chart (Kindergarten Chart). Increased time spent by a child on a screening can create more anxiety, lack of cooperation and fatigue . Typically, vision screenings are done at the beginning of a visit as part of the nursing assessment. By using a screening tool that is not only easier for the patient to complete, but also reduces time spent is beneficial for both the patient and the flow of the clinic visit. The more efficient a clinic visit is, the more opportunity there is to see additional patients which is a need within a clinic that is providing free services.
Additionally, ensuring that the nursing students administering the exams are doing so in a reliable manner is imperative to positive outcomes. Every clinic day has a different group of students, therefore, having the standardized process in print and available for review is imperative to validity. The primary investigator also demonstrated the proper administration of the vision examination process to the students and a return demonstration was completed to ensure adequate understanding. The use of cost effective eye occluders that can be cleaned and reused between patients leads to long term benefits by ensuring proper examination, while also lowering the financial burden on the limited resources of the clinic. By completing the screening at ten feet as recommended for the LEA symbol chart, interruptions are decreased, and the children can focus on the task at hand. These are all simple changes that can make an impact on the ability to provide effective vision screenings. The implementation of a standardized vision screening process that is adapted to a specific population can be done while concurrently following evidence - based practice guidelines provided by organizations such as the AAP and National Center for Children’s Vision & Eye Health. These guidelines have numerous studies supporting their efficacy but have yet to be studied in all patient populations or implemented through policy.
Specifically, within the SPN clinic, a change in practice could be implemented given the results of this study. The LEA symbol chart could be adopted as a new screening tool used for vision screenings. A study on a larger scale could also be completed to determine effectiveness of the adapted vision screening process in children who speak other foreign languages or have an intellectual disability. It would also be beneficial to further explore how to adapt this screening process to obtain better results in children three and four years old given that lack of cooperation has such an impact on measured outcomes. Being that this was a pilot study; the sample cannot necessarily be generalizable to a larger population. However, the primary goal of the study was to determine an optimal screening process for a specific population in need. That is not to say that this cannot be replicated on a larger scale and potentially utilized in other healthcare settings that care for a similar patient population. The study data was also collected on a single day and utilized a convenience sample from the clinic, which limits the reliability measure.
While the implementation of a standardized process is
beneficial to gathering accurate measurements, many other barriers to care
exist to improving overall preventative care. “Low primary care screening rates
and inadequate rates of referral and completion of an ophthalmologic
examination indicate that a different screening device will not in itself
result in optimal detection and treatment of vision loss. Rather, improvements
are needed in the entire process of preschool vision screening in the primary
care setting, from screening to definitive diagnosis and, ultimately, to successful
treatment” . This study begins to examine the needs of a unique patient
population as it relates to pediatric vision screenings. It presents an
evidence - based intervention that is a plausible option for improving the
efficacy of vision screenings. Further studies examining proper referral and
follow up needs is required to establish a comprehensive solution to the
various additional barriers faced by this population to ensure adequate
well-rounded care and improved psychosocial outcomes for children facing
disparities in health care access.
you to the University of Pittsburgh1 School of Nursing, University
Honors College, and all of the University of Pittsburgh professors on my
committee who aided in this research. As well as Robert Morris University2
professor Dr. Carl Ross. Special recognition to Dr. Diego Chaves - Gnecco for
creating Salud Para Niños and all the dedicated volunteers for their
cooperation and unwavering work for the community. All procedures performed in
this study was approved by the Institutional Review Board (IRB#: PRO15110217).
Conflict of Interest
conflicts of interest.
Table 1: Completion Rate.
141.8 seconds (2
minutes and 21 seconds) ± 45.7 seconds
100. 7 seconds
(1 minute and 40 seconds) ± 33.8 seconds
Table 2: Time.
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