The demographic transition model illustrates the stages from which a country with high birth and death rates transform into a country with low birth and death rates. The model, based on population stages in several industrialised countries in western Europe and North America, suggests that all countries pass through similar demographic transition stages or population cycles or will do given time. This usually occurs along a series of stages. EMDCs have already gone through this phase since the advent of the Industrial Revolution while ELDCs have begun the stage much later or are still in the process of undergoing this stage.
Crude Birth Rates and Crude Death Rates
The Demographic Transition Model is based on the changes seen in the birth and death rates (per 1000) over time and relating them to the overall population change. Usually taking the number of births in one year and dividing it by the number of deaths and then multiplying it by 1000 calculate the figures. EMDCs have a lesser CBR and CDR compared to ELDCs.
Usually the birth rate and the death rate mirror each other in relation to the stage of development of that particular country. However, this trend can be influenced by particular dramatic events such a natural hazards, wars and disease. The first stage is illustrated by high death and birth rates and symbolise a country in its premature phase.
The second stage represents a decline in rates and this is as a response to improving countries or the improving development stage of a particular area. Over time children became an added expense and were less able to contribute to the wealth of a family and along with advances in birth control the birth rate was reduced. Populations grew but not near the level as would occur in stage one.
Stage three is mostly associated with developed countries. The birth and death rates are low although the CBR still continues to outnumber the CDR.
Like all models, the demographic transition model has its limitations. The model fails to account for other factors such as migration that is a major influence on the patterns of population distribution. Immigration accounts for much of the numbers of population growth in EMDCs.
The model does not identify that, in some western countries (Sweden and Germany), the birth rate as fallen below the death rate. This has actually caused a population decline and is often referred to as the fifth stage in the transition model.
The model does not also provide guidelines stating how long a country is to progress to the next stage. Some countries took centuries such as France whilst the Tiger countries of Asia literally transformed within a matter of decades. The model also avoids acknowledging that some countries in earlier stages do have low birth rates that are enforced through religion of government as in the case of Chinas 20th Century One child policy. Additionally, because the model is Eurocentric it fails to recognise that some countries in the developing world may fail to even pass through all of the stages outlined in the table.
The model assumed that the fall in the death rate in Stage 2 was the consequence of industrialisation. Initially the death rate in many British cities rose, due to the insanitary conditions that resulted from rapid urban growth, and it only began to fall after advances were made in medicine. The delayed fall in the death rate in many developing countries has been due mainly to their inability to afford medical facilities. In many countries, the fall in the birth rate in stage 3 has been less rapid than the model suggests due to religious and/or political opposition to birth control (Brazil), whereas the fall was much more rapid, and came earlier, in china following the government-introduced one-child policy.
Therefore, it does have its uses however it is also limited in its practicalities because of the aforementioned factors. The model can be used to show how the population growth of a country changes over a period of time and to compare rates of growth between different countries at a given point of time.
Optimistic and Pessimistic population growth