What is Demography in Community Medicine / PSM

This is an animated video lecture on the Chapter DEMOGRAPHY from the PARK Textbook of Community Medicine.






Hi...welcome to abmbbs....one of our subscribers....Dr. Ayesha Iqbal...had asked for a video on the chapter of “Demography” from the PARK TEXTBOOK of COMMUNITY MEDICINE....so this video is made on her request.....

Now the 1st thing you should know about this chapter is that PARK contains a lot of data on the current demographic status of india....these numbers keep changing from year to year & from edition to edition....I will be dealing with them in another video...in this video I will be talking about the basics & core concepts of demography which does not really change much.

So what is demography? Demography is the scientific study of human popuation...
What are the different demographic processes...fertility, marriage, mortality, migration &.....social mobility.

Next we come to Demographic cycle....As you can see it has 5 stages...High Stationary, Early Expanding, Late Expanding, Low Stationary & Declining.....The high stationary stage has both high birth rate & high death rate...so they end up cancelling each other...& the net population remains constant...India was in this stage till 1920........Next.......is the Early Expanding stage....here the birth rate remains high but the death rate declines...possibly due to better healthcare facilities..so..the net population increases....Next is the Late Expanding Stage.....here the death rate declines further but the birth rate also starts declining....so in total the population still continues to grow,.....India now belongs to this stage...........Next is the Low Stationary Stage....here both the birth rate & death rate decline & they both cancel each other....so the net population remains constant......Finally there is the Declining Stage....here the net population begins to decline because birth rate is lower than death rate....Germany & Hungary are currently in this stage....

Next we come to this graph....this is not given in PARK but I feel everybody should know this graph because it helps to understand the concept of Demographic Cycle better......the numbers here denote the stages ....the pink line stands for the birth rate , the blue line shows the death rate &.....the red line denotes the total population....so...once again quickly....in the 1st stage or high stationary stage the birth & death rate is high, so the net population is constant....in the 2nd stage or Early Expanding Stage the death death rate decreases but the birth rate remains constant...so net population increases...in the 3rd or Late Expanding Stage the birth rate begins to decline but the net population still continues to rise...4th stage or Low Stationary Stage stabilizes the population & finally the 5th or Declining Stage causes the population to decline because birth rate goes below death rate...

Next tell me what is demographic window? It is that period of time in a country when the working age population is more...that is when people above 65years denote less than 15% of the population & people below 15 is less than 30%....India will be in this stage from 2010 to 2050....

Next is Demographic trap....It is that time when population growth is high due to high Birth rate & low Death Rate.....it basically denotes stage 2 of the demographic cycle

Next we come to some definitions...it can get a bit boring for the next 45 seconds but trust me its important....1st is Crude Birth rate...it is the number of live births per year per 1000 mid year population.
Crude Death Rate is the number of deaths per year per 1000 mid year population.
Annual Growth Rate is Crude Birth Rate – Crude Death Rate
Finally Growth Ratio is Growth Rate X 100