Answer to Problem on Pancreaticoduodenectomy and Surgical Apgar Scores

We have 3 independent comparison groups (Surgical Apgar Score) and a categorical outcome variable (morbidity/mortality). We can run a Chi-Squared test of independence.

Step 1:

H₀: Apgar scores and patient outcome are independent of one another.

H_A: Apgar scores and patient outcome are not independent.

Step 2:

equation image indicator (We were given the chi-squared value)

Step 3:

equation image indicator

Therefore reject H₀ if equation image indicator

Step 4:

Chi-squared = 14.3

Step 5:

Since 14.3 is greater than 9.49, we reject H_0.

_{There is an association between Apgar scores and patient outcome. The lowest Apgar score group (0 to 4) experienced the highest percentage of major morbidity or mortality (16 out of 57=28%) compared to the other Apgar score groups.}

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