Vision Screening Principles: Key Terms in Medicine

When should you screen?

During stage of subclinical disease (underlying measure but before symptom onset)

Screening

presumptive identification of individuals in a defined population at risk likely to be affected by an asymptomatic or subclinical condition who can benefit by being further investigated

Vision screening clinical definition

tool that allows for possible identification, but not diagnosis, of eye disease and conditions

Vision screening functional definition

a method to identify potential problems or irregularities with the visual system so that a referral can be made to an appropriate eye care professional for further evaluation

Increase the proportion of preschool children aged 5 years and under who receive vision screening (Health People 2020)

Baseline: 40.1 Target-44.1

Screenings are a form of what type of prevention

secondary prevention

What specific populations should receive screenings

in populations that have an absence of adequate resources; generally for higher risk populations; geographically isolated areas

Outcome of screenings

cannot diagnose but can be used to expand entry to the health care system

Benefits of screenings

less expensive and less time-consuming

Downsides of screenings

sensitivity and specificity of screenings are not as good as eye exams

What is Ohio's pediatric vision screening requirement?

Just school-age only. Have one in kindergarten and every odd grade or any new students

Number of states with vision screening requirement for pre-k

26 states

Number of states that have vision test requirement before kindergarten

4 states

Follow-up frequency after screenings

Can vary widely from 29% to 100%; need effective processes to help access follow up care

State of Ohio Referral Rate and Completed Referral

2017-18: R- 9.6 C-31.56

2018-19: R-8.57% C-22.50%

2020-21: R-9.46% C-19.58%

States that require vision screening test to require what type of screening

Distance Visual Acuity

Biggest predictor for receiving follow up care after screening

health insurance

Technology and screenings

telemedicine for screening, evaluation, and diagnosis of eye disease and internet technologies for patients and their families to take a greater role in monitoring of their chronic disease conditions thus reducing the need for more frequent follow-up visits

3 criteria for a screening

1. Identification of disease

2. Disease is previously unrecognized

3. Procedures to detect the disease are quick and testing is easy

Principles of Screening

Target population, conditions to be screened, marketing program to promote, uniform and valid screen protocol, referral criteria, referral mechanism, measurable variables to analyze benefits

Types of screenings for population

opportunistic, mass, or targeted

What makes a condition a good one to screen for?

High prevalence, public health burden, a quick, accurate, painless and reliable screening test, chronic, asymptomatic, treatable, prognosis is better when detected earlier, cost effective if treated early

Visual conditions that meet screening criteria example

Ambylopia

Leading cause of VI in children

Ambylopia

Risk factors for amblyopia

high ametropia, anisometropia, deprivation, strabismus, genetic

Stereopsis test can detect

Strabismus, Ambylopia, Anisometropia, High Refractive errors, Diseases affecting the visual acuity in one or both eyes

Sensitivity

proportion of diseased individuals that test positive by the screening

Specificity

proportion of disease-free individuals that test negative

False positives

proportion of people who tested positive, but are disease free

False negatives

proportion of people who tested negative, but are disease positive