About the Data
Basic Screening Survey (third grade)

The Basic Screening Survey is a non-invasive, open-mouth survey developed by the Association of State and Territorial Dental Directors (ASTDD). The survey assesses and monitors the oral health status of four key populations (i.e., children in Head Start/Early Childhood programs, kindergarteners, third graders, and older adults).  This page contains information about the Third Grade Basic Screening Survey.    

  • Oral health status of third grade students in Minnesota public schools as measured by the prevalence of:
    • Caries experience (untreated or treated tooth decay).
    • Untreated tooth decay.
    • Treated tooth decay (restored or filled).
    • Dental sealant on at least one permanent molar tooth.
    • Treatment urgency (none, early care, urgent care).
  • Oral health disparities among third grade students in Minnesota public schools by:
    • Demographic groups (i.e., sex, race and ethnicity).
    • School factors (i.e., urban or rural location, total student free and reduced price lunch eligibility rate).  
  • Untreated tooth decay can lead to difficulty speaking, chewing and swallowing, loss of self-esteem, pain, and missed school days.
  • Application of dental sealants may prevent tooth decay.
  • Create awareness among educators, dental, medical and public health professionals, researchers, grant makers, policy makers, and the public on the oral health of Minnesota third graders in public schools.
  • Provide statistical evidence to support state and local program planning, evaluation, and policies.  
  • Target prevention efforts and resources towards groups or geographies identified as having higher rates of untreated tooth decay or low sealant rates (i.e., certain racial and ethnic groups, rural schools, or schools with higher free and reduced price lunch eligibility).
  • Dental or oral health services provided within schools.
  • Prevalence of caries experience (untreated or treated tooth decay), untreated tooth decay, treatment urgency, treated tooth decay, and dental sealants among all Minnesota public school students.     
    • All Minnesota public school students enrolled (2013 to 2014 school year):
      • 836,207 enrolled.
      • 322,000 eligible for the free and reduced price lunch program (38.5%).
  • The data only represent Minnesota third graders in public schools during the 2013 to 2014 school year.
  • Household income or poverty status of individual children who participated in the survey. 
    • The Minnesota Department of Health Oral Health Program collected and analyzed data indicators by total student free and reduced price lunch eligibility within survey sample schools. 
    • Student eligibility for the free and reduced price lunch program is an alternative measure to identify the percentage of children within public schools from lower income households.  This is not an actual measure of the percentage of students in poverty enrolled in a school, as that data is not automatically collected.  

In 2015, the Minnesota Department of Health Oral Health Program in partnership with oral health providers carried out the Third Grade Basic Screening Survey in Minnesota. 

Type of study: Descriptive, Cross-sectional.  The Oral Health Program assessed oral health measures and demographic factors during the same time period.     

Sampling method: The Oral Health Program used the ASTDD recommended sampling methodology.  In 2015, the Oral Health Program used stratified probability sampling to increase precision of estimates and to reduce selection bias. The sampling frame included all Minnesota public schools. Two variables used in implicit stratification were: (1) urban or rural school location and (2) total proportion of student free and reduced price lunch eligibility within schools.  

The Oral Health Program systematically sampled 50 schools with a random start and a constant selection interval from the sorted school list.  Then, the Oral Health Program selected public schools with 10 or more children in the third grade. All third grade students within the final participating public schools sample were given the opportunity to be screened/surveyed. 

Sample size: 50 public schools in Minnesota with 3,199 third graders screened. 

Data collection:

Licensed dental hygienists and volunteers were trained in ASTDD screening protocols and calibrated in the use of the Basic Screening Survey instrument to collect data on the oral health status of Minnesota third graders enrolled in public schools. 

  • Oral health status of participants (prevalence estimate) as measured by:
    • Caries experience (untreated or treated tooth decay).
    • Untreated tooth decay.
    • Treated tooth decay.
    • Dental sealants.
    • Treatment urgency.
  • Parent or guardian reported demographic information on participants:
    • Age.
    • Sex.
    • Race and Hispanic ethnicity.

Oral Health Program staff collected the following school demographic information:

  • Urban or rural status.
  • Free and reduced price lunch (FRPL) eligibility rate.
    • Low (25.0% or less FRPL).
    • Mid-low (25.1 to 50.0% FRPL).
    • Mid-high (50.1 to 75.0% FRPL).
    • High (more than 75.0% FRPL).

Analysis: Data analysis followed guidance from the Association of State and Territorial Dental Directors (ASTDD) (PDF).  The sampling design was a stratified probability sample used to increase precision of estimates and reduce selection bias.  A weight factor = (# of children in sampling interval) / (# of children screened in sampling interval) was created in Citrix SAS statistical software and applied equally to each child within a particular school.  

Caries experience: a measure of past and present tooth decay defined as the presence of either untreated or treated (restored or filled) tooth decay.  Caries is the disease that causes tooth decay and can lead to cavities in teeth.

Untreated tooth decay: refers to tooth decay that has not been treated (restored or filled).

Dental sealant: a plastic resin material applied to the biting surfaces of molars and premolars (back teeth) as a strategy to prevent tooth decay and cavities.

Treatment urgency: refers to how soon a person should visit the dentist for clinical diagnosis and any necessary treatment.  Treatment urgency has three categories.

  • None: the patient has no obvious problems.  The patient should follow regular dental check-up schedule. 
  • Early care: the patient has untreated tooth decay, but no signs or symptoms that include pain, infection or swelling.  The patient should seek dental care within several weeks. 
  • Urgent care: the patient has untreated tooth decay and signs or symptoms that include pain, infection, or swelling.  The patient should seek dental care as soon as possible. 

Caries experience

The number of third grade students screened with untreated or treated tooth decay (caries experience) divided by the total number of third grade students screened, multiplied by a weight factor*, multiplied by 100 percent.

Untreated tooth decay

The number of third grade students screened with untreated tooth decay divided by the total number of third grade students screened, multiplied by a weight factor*, multiplied by 100 percent.  

Dental sealant

The number of third grade students screened with at least one dental sealant on a permanent molar tooth divided by the total number of third grade students screened, multiplied by a weight factor*, multiplied by 100 percent.

Treatment urgency

The number of third grade students screened with untreated tooth decay and determined to have an early or urgent treatment care need, multiplied by a weight factor*, multiplied by 100 percent. 

*Note: Weight factor = (number of third grade students enrolled in sampling frame) divided by (number of third graders screened in sampling frame)

  • Third grade students in Minnesota public schools (2013 to 2014 school year):
    • 63,444 enrolled.
    • 26,777 eligible for the free and reduced price lunch program (41.3%). 
  • Causal factors cannot be determined, only associations between factors and outcome measures.
  • The cross-sectional study design does not identify whether dental sealant placement occurred before or after the occurrence of caries experience (untreated or treated tooth decay).
  • Parental and guardian consent is required for participation in the Basic Screening Survey.  Any correlation between consent and outcome measures may bias results.  

Minnesota Department of Health Oral Health Program (2015).  Third Grade Basic Screening Survey.  Collected by the Minnesota Oral Health Program.  St. Paul, Minnesota: Accessed from MN Public Health Data Access Portal. [Add URL] Retrieved month, year.