Cross Sectional Study

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Cross Sectional Study

• Judith V. Sunga-Montalbo, RND

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Definition

• Cross sectional study
• an observational study ( using basic senses to
  gather data )
• examines a characteristic or set of
  characteristics in a set of subjects at one point
  in time ( prevalence )
• a snap shot of characteristic or condition of
  interest ( may result to misleading conclusions
  if interest focuses on disease or time dependent
  process )

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• also called a survey ( collection of opinions )
  or poll ( a questionnaire administered to a
  sample of people, often about a single issue ).
• A study that is quick and inexpensive to
  complete.
• Designed to determine what is happening ? right
  now

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Example Breast feeding and obesity cross
sectional study

• Abstract
• Objective To assess the impact of breast
  feeding on the risk of obesity and risk of being
  overweight in children attending school in
  Calima. In a sample of 80 children, early
  feeding, diet, and lifestyle factors were
  assessed using responses to a questionnaire
  completed by parents.

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• Subjects 80 children aged 9 and 10, all
  Filipinos
• Main outcome measures
• height and weight measurement
• BMI calculation kg / height (m) ²
• Being overweight was defined as having a body
  mass index above
• male 18.86 for 9 y/o
• 19.61 for 10 y/o

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• female 19.2 for a 9 y/o
• 20.2 for a 10 y/o
• REFERENCE International Reference
• ( NCHS ) BMI for age
• Questionnaire Was your child breast fed? ,
  How long was your child exclusively breast fed
  ?
• Other questions number of siblings, parents
  ages and educational attainment, childs health (
  LBW ),
• Early feeding, frequency of eating selected foods

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Statistical analyses

• The prevalences of overweight and obese children
  were calculated according to the duration of
  breast feeding.
• x² tests ( ex. chi-square, Mcnemar ) were used to
  compare breast fed and non-breastfed children
  and their association to an obese/overweight
  child.

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• Exclusive breast feeding was defined as the child
  being fed to no food other than breast milk.
• Results The prevalence of obesity in children
  who had never been breast fed was 4.5 as
  compared with 2.8 in breast fed children. A
  clear dose response effect was identified for the
  duration of breast feeding on the prevalence
• of obesity

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• The prevalence was 3.8 for 2 months of
  exclusive breast feeding, 2.3 for 3-5 months,
  1.7 for 6-12 months, and 0.8 for more than 12
  months.
• Breast feeding as a significant protective
  factor against obesity development.
• Similar relations were found with the prevalence
  of being overweight.
• The protective effect of breast feeding was not
  attributable to differences in social class or
  lifestyle.

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• Conclusions
• Prolonged breast feeding may help decrease the
  prevalence of obesity
• in childhood.
• Since obese children have a high risk of becoming
  obese adults, such preventive measures may
  eventually result in a reduction in the
  prevalence of cardiovascular diseases and other
  diseases related to obesity.

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• Salamat po!