How to Compute & Recode SPSS Data. Video at https://youtu.be/QrE6SuxYAuQ

1. Compute & Recode
SPSS Data
http://www.palmx.org/drtamil/spss/sga-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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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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Recode and transform to do test
 We were asked to conduct the appropriate
statistical test to test whether there is any
association between “Classification of
Weight” (OBESCLAS) and SGA
(OUTCOME).
 So we need to compute weight and height
into BMI, then recode BMI into
classification of underweight, normal and
overweight.

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Steps to recode
To compute Body Mass Index
 formula Weight/Height2
◦ Weight in kg
◦ Height in m (so need to change ours from cm
to m by dividing with 100)
Then recode BMI into Classification of
Weight
 <20 Underweight
 20 to 24.99 Normal
 25 & > Overweight

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https://youtu.be/QrE6SuxYAuQ
Click on
“Compute
Variable”

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Type in the variable name/label

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mBMI=weight/(height/100)**2

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New variable mBMI created

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Recode
 Underweight; 0 – 19.99 ->1
 Normal; 20 – 24.99 ->2
 Overweight; 25 – Infinity ->3

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Recode into Different Variables

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New Output Variable

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Recode old into new values

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Recode old into new values

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Recode old into new values

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New variables created

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Relabel new variable