A longitudinal research is a form of research that is used for an extended period of time. The advantages are that it will create in depth-analysis of a particular subject, however there are many disadvantages that follow. The main victim of this form of research is on positivists. One main disadvantage is the practicality of the research. Since the research is over long period of years, it will be very expensive to run and takes up a huge part of a researcher’s life.
For example the 7 up documentary is still running to this day from 1964 and this shows the impacts it has on the researcher. The researcher must still have interest on the subject otherwise the research will become unrepresentative. Furthermore, since it’s a very long study some participants may want to opt out of the research especially if they started when they were young since they could have been forced in. This is called subject attrition and this affects the reliability and representativeness of the research as less people will share their opinions.
This is seen in Douglas’ study where more than 500 participants decided to drop out of the research. Another disadvantage is a possible chance of the Hawthorne effect. Especially if the research is documented like the 7 up series, participants will want to make themselves sound more plausible in the audience’s eyes and therefore behave differently to their normal selves. This will create a massive flaw in validity, as it does not reflect their true emotions and feelings.
This problem is further pushed by the fact that the researcher could ‘go native. ’ This is where the researcher becomes too actively involved meaning that they start conforming to their participants beliefs. This will greatly affect validity and reliability as the researcher will have an element of bias when they start to understand other people’s beliefs. There are many theoretical issues with the research also. Comparability and reliability becomes an issue as it can be affected through the change in the researcher and research design.
This is because when a research has begun, changing the research method half-way through will damage reliability as different results will be given. Furthermore, repeated questioning over a long period of time means that participants can form new ideas and change opinions which threatens validity as their ‘true picture’ of social reality changes. Ethical issues are also a factor. Since they are a form of research done over a long period of time, participants tend to start at a young age.
Therefore although parents may have given consent, the participants themselves should be able to withdraw if they wanted to. The fact that researchers could evade privacy by asking them personal questions about their lives will also be an ethical problem. Although this form of research is good for interpretivists, positivists do not agree with this method. This is because it produces qualitative data and therefore patterns and trends can’t be spotted directly to create a solid explanation.
Furthermore it will take longer and be harder to analyse especially with the long span of the research but also the tendency of having a larger number of participants. Overall, longitudinal research has its advantages but there are quite a number of disadvantages. The fact that reliability, validity and representativeness is affected could show that this form of research isn’t particularly viable and other forms such as life histories or case studies should be taken into account.