How to run Pearson's Chi-square for SPSS

1. Running Pearson Chi-
Square on SPSS
http://www.palmx.org/drtamil/spss/
sga-ttest-youtube.sav

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Factors Affecting SGA
SGA
(Y/N)
(Birth
weight)
Mother’s
Nutrition
(BMI/Obesity)
•Weight
•Height
Smoking
Hypertension

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Dependent Outcome
 Birth weight of the babies
 Small for gestational age i.e. less than
2.7kg for term babies – Y/N
By Yehudamalul - Own work, CC BY-SA 3.0,

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Suitable statistical test
 Conduct the appropriate statistical test to
test whether there is any association
between “Classification of Weight”
(OBESCLAS) and SGA (OUTCOME).

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Factors Affecting SGA
SGA
(Y/N)
(Birth
weight)
Mother’s
Nutrition
(BMI/Obesity)
•Weight
•Height
Smoking
(Y/N)
Hypertension
(Y/N)

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OBESCLAS Versus SGA
 Weight is classified into
◦ Underweight
◦ Normal weight
◦ Overweight
Therefore it is categorical data.
 Outcome is categorized into Yes (SGA
babies) and No (Normal babies)
Therefore it is categorical data.
 With n=200, most suitable test is Pearson
Chi Square.

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Cross-tabulation Table

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Cross-tabulation Table

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Pearson Chi-Square

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Pearson Chi-Square

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Conclusion
 A clear decrease rate of SGA as the
weight of the mother increases.
 The difference is statistically significant
since p value smaller than 0.05.
 Therefore there is a significant increase
rate of SGA as the mothers’ weight
classification decreases from overweight
to underweight.

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Exercise
 Repeat the same statistical test between;
◦ Smoking and Outcome
◦ Hypertension and Outcome