This convenience-based sample, pilot cross-sectional study was conducted at the three highest attendance, outdoor public pools associated with the Seattle and the Snohomish Departments of Parks and Recreation in WA. Participating pools were conveniently selected due to their location and schedule throughout the week. While they also offer lap swimming and learn to swim sessions, participation was restricted to those families visiting the pool to relax or have fun during the open swim sessions.

Parents with school-aged children attend the open/public swim sessions at these pools, which charged an entrance fee (≤$4.00 USD) and required children (≤17 years) to pass a life-guard administered in-water swim-test before entering the deep end. Open/public swim sessions allow patrons to freely enjoy swimming or playing in the water, different from lap swimming and learn to swim teaching sessions.

Between 3–8 trained interviewers collected data at 1–2 pool locations during July 8–30, 2014, coinciding with the beginning of school-children’s summer vacation break. Interviewers approached potential participants (e.g., adults with children who appeared to be 7–17 years old) outside the pool, while waiting to buy tickets or for the open swim session to start. Adults were invited to participate, and screened for eligibility (i.e., inclusion and exclusion criteria).

Parents completed the parental consent and permission form. Subsequently, a second interviewer verbally explained the study to the child. If the child assented, parents and children were interviewed simultaneously during approximately 5 minutes, yet separately to avoid their influencing each other’s responses. They were reunited once both finished answering the questions.

Child and parent survey responses, and child swim-test result data were linked and analyzed using Epi Info 7.1.1.14 and SAS v. 9.3. Cross-tabulations were used to describe the sample, and identify any differences (N, %, X²) by 3 sub-groups of child/parent dyads:

In total, 775 families were approached. Of the 586 eligible families, 82% agreed to participate. The final sample size was 482 child/parent dyads. The majority of the dyads were swim-tested (63%, n=305); 85% of them passed.

Most children were 7–10 years old (median=9 years), non-Hispanic White (72.4%), and represented both genders equally (Table 1). Significantly more non-Hispanic White children (79.7%) had previously been swim-tested (X²=11.40, p=0.003; Hispanic=5.7%; non-Hispanic Other=14.6%). Swim-tested children were slightly older (median=10 years) and of non-Hispanic White (87.1%) parents/guardians (non-Hispanic Other 9.6%; Hispanic 3.3%; X²=9.79, p=.0008) (data not shown).

Parents/guardians’ were on average 44 years old, mostly female (74.9%) and non-Hispanic White (83.2%). Most parents/guardians completed a bachelor’s degree or higher (73.9%), and 47.9% of the dyads reported an annual household income of ≥$100,000 (Table 1). More swim-tested (51.5%) than non-swim-tested (41.8%) dyads reported ≥$100,000 annual household income (X²=9.17, p=.01) (data not shown).

Most parents/guardians self-reported that they “know how to swim” (95%), had “ever taken swim lessons” (73.2%), and felt “comfortable in water over head” (87.5%). Females accounted for the majority of parents/guardians who did not feel comfortable in water over their heads (93.3%, X²=12.45, p=.0004) (data not shown).

Total paired sample (N=482) data were analyzed to evaluate agreement between children and parents/guardians’ responses within each dyad (Table 3).

Among swim-tested dyads (N=305), passing the in-water swim-test positively correlated with child/self and parental reports of the child having “good swim skills” and feeling “comfortable in water over head”. Perceived “good swim skills” most strongly correlated with passing the in-water swim-test, especially if the parent/guardian was the informant (r=0.28) and the parent/guardian also reported not being comfortable in water over head (r=0.41). The “ever taken swim lessons” measure did not significantly correlate with the child passing the in-water test, regardless of the informant. Therefore, it was excluded from the remaining analyses (Table 4).

Unlike previous studies, this non-generalizable, convenience sample study benefits from the collection of data on children’s swim skill via multiple methods: in-water swim-test results, child/self- and parental reports. Previous studies have found moderate or weak correlations between young adult’s self-perceived and in-water swim skills.[15 16] To our knowledge, this is the first study in the U.S. that compares children’s self/proxy-reported data with results from a basic in-water swim-test to validate swim skill surveillance measures. Valid population swim skill data could identify vulnerable populations, inform the development of drowning prevention and learn to swim policies and programs, and help organizations that promote swimming and learning to swim to evaluate their programs’ reach and effectiveness.

Various skills have been suggested to establish water competency.[17] Based on an international survey of recreational aquatic organizations, the American Red Cross defined swim competency as having skills in entering, submersion and surfacing, propulsion, turning, floating/treading, and exiting from water.[18] Contrastingly, Dixon et al. identified 7 swim competency domains, based on young adults’ perceptions (i.e., not panicking; instinctive, basic, advanced, and rescue skills; covering a distance; ability to swim in multiple settings).[19] It is generally agreed that swimming involves propelling oneself some distance without aid, yet research has not yet defined what is the minimal distance and skills necessary to prevent drowning. Some validated programs outside of the U.S. suggest 25 meters and some specific skills to reduce the risk of drowning. [7 20]

Similarly, we observed variability in the pool’s minimum swim-test passing criteria. While all pools required children to traverse ≥25 meters (82 feet), the specific distance differed based on each pool’s dimensions. Parents and children advised that lifeguards’ enforcement of the pools’ objective swim-test passing criteria also varied, potentially affecting this study’s findings.

Establishing consistent criteria for day-to-day operations across different sites is challenging. Nonetheless, future studies could benefit from consistent swim-test criteria across water venues.

Pool administrators confirmed that our study participants were representative of the patrons at these three specific pools (e.g., mostly non-Hispanic White, high income, highly educated). Yet, they were not representative of Washington’s diversity. Findings cannot be generalized to all of WA, all population groups (especially racial/ethnic minorities, and non-English- or Spanish-speakers), the US, or other geographical or cultural contexts. Additionally, older children were under-represented, primarily because their parents/guardians were not present; the sample is skewed towards younger children (median: 9 years). Sampling limitations impeded reliable analyses by socio-demographic characteristics.

Participants were a convenience sample of pool-attending families, whose children likely learned how to swim at community pools (63% of those who had ever taken swim lessons) and whose parents were actively engaging with them in water recreational venues. Children who voluntarily chose to be swim-tested could have had more opportunities to obtain swim skills, knowledge, and confidence to pass the swim-test than the general population. In fact, the child’s lack of swim skill or confidence, and/or fear of failing were frequently mentioned as reasons for not taking the test. This sample bias, and the fact that passing a swim-test does not confer total protection against drowning, [21] must be considered. Furthermore, passing an in-water swim test at a controlled environment (i.e., pool) does not necessarily imply the child possesses the water competency required in open water or other natural water venues (e.g., beach, rivers).

This convenience-based sample, pilot study serves as a first step in the validation of survey child swim skill measures commonly used in public health surveillance. Parent’s perception of his/her child having “good swim skills” was the measure that most correlated with observed swim skill among participants.

Findings are limited to the population commonly served by the participating pool venues in this study – mostly non-Hispanic White, highly educated, high income families with active parental participation in children’s swimming activities. Future studies need to evaluate the validity of swim skill measures among diverse populations, which could be reached at open water and free-admission venues. Additionally, strategic collaborations with after school programs, schools, and summer camps could increase the participation of older children and those who attend public water venues without a parent present. Findings can help pool operators develop consistency in swim-test criteria and administration, which is important for both safety and research purposes. Additionally, it is recommended that future studies incorporate verbal or pictographic descriptions of what it means to know how to swim to ensure respondents have a clear understanding on what it means to know how to swim prior to answering swim skill surveillance questions.