In a study examining the relationship between school size and oral health status among high school children, data were collected from 500 students across 10 schools. Schools were classified into small (fewer than 300 students), medium (300-600 students), and large (more than 600 students) categories. Oral health status was measured as "good", "average", or "poor" based on dental checkups.

A cross-tabulation was conducted to analyze the relationship between school size and oral health status. The results showed that in small schools, 60% of students had "good" oral health, compared to 40% in large schools. Large schools had a higher proportion (45%) of students with "poor" oral health. Medium schools were in between, with 50% of students having "average" oral health.

A chi-square test of independence was applied to determine if the association between school size and oral health status was statistically significant. The p-value was 0.03, indicating a significant relationship between the variables (p < 0.05) (McHugh, 2013). This suggests that school size might influence oral health outcomes, possibly due to differing access to resources or health programs.

Question is?

WHAT IS THE EFFECT SIZE CALCULATION APPROACH FOR THE ABOVE SCENARIO?