WRAP IAS Write · Read · Analyse · Practice
Mains Prelims
0 Log in to start a streak. Daily practice. Sign up Login

Q5(c) · UPSC Civil Services Mains 2015 · Anthropology GS 1 · 10 marks · 1 min read

Longitudinal method of studying growth.

Topic: Distinction between technique, method and methodology. Syllabus: (b) Distinction between technique, method and methodology Same official PYQ from year-wise 2015 and Distinction between technique, method and methodology.

Download PDF Get this answer evaluated →

Revision summary

Longitudinal method repeats measures on the same children. It reveals tempo and peak height velocity. Tanner’s Harpenden study is the classic. Cross-sections are cheaper but mix early and late maturers. Dropout and secular change are the main limits.

Model answer

Introduction

A longitudinal growth study measures the same children again and again. It is the method that can see tempo, not only size.

Body

How it works

  • Height, weight, and skeletal age are taken at fixed intervals on one cohort.
  • Tanner at Harpenden showed spurts, peak height velocity, and individual tempo that a one-time survey misses.
  • Indian series, such as work associated with ICMR and university auxology units, used mixed-longitudinal designs when pure follow-up was costly.

Contrast and limit

  • Cross-sectional studies are cheaper and map a population at one date. They smear early and late maturers together.
  • Longitudinal work suffers dropout, secular change during the study, and ethics of repeated X-rays.
  • The method is gold for velocity curves; it is poor as a quick census.

Flow diagram

flowchart TD
  L[Longitudinal] --> S[Same child over time]
  S --> V[Velocity spurt]
  C[Cross-section] --> Z[Size at one date]

Conclusion

Longitudinal growth study follows persons through time. Tanner-style velocity is its yield; cost and attrition are its price.

Quick related

Students also ask

  • Can a school survey replace it?

    A survey gives status. It cannot give a true velocity curve for each child.

  • Why not X-ray every visit?

    Radiation and consent limit skeletal-age films. Height remains the workhorse.

Toppers' copies

Toppers' copies for this question will be uploaded soon.