There is no test that will reveal somebody's personality who has all his five senses intact; personality for any normal human being is bound to change depending on time and space.If a person will react the same way to any action at different times and at different places something is either wrong with the times he reacts or with the places where he reacts. Since these two cannot be wrong all the time my opinion is that the format of these tests should be revised.
Words mean different things to different people; the reason I will call a person a friend will not be exactly the same reason you will call another person a friend. For this reason, our answers in a personality test question that has to do with friendship are not bound to be the same. For example, john may consider Peter his friend because he dropped him off at work one time, James may not consider Peter as a friend yet he drops him off at work everyday. More to this. Some of the questions contain some words whose meaning the examinee does not know, yet he has to choose an answer.
Furthermore some of the questions, as I have learned, are to find out whether one is an outgoing person or not( introvert versus extrovert). Human behavior and character should not be reduced to the Mathematical formula where two plus two is four and nothing over. Different work places have different guidelines to be followed in case of an abnormal happening. The last personality test I took asked what I would do if something happened at my work location and it was not my business. Out of the four answers from which I had to choose none was close nor even similar to any of the things I had been instructed to do at my previous jobs. One's personality does not always depend on what has been or he is; it has been molded by the guidelines of the companies for which he has worked before.
I have taken seven personality tests in my life and I have never passed any. The problem is with the way these questions are set. To test one's personality they don't have to narrow down the sphere of his reasoning or reaction with a multiple choice type of test. To better test anybody's personality, in my reasoning, is to give certain conditions and ask him/her to write an essay-like answer to what he/she would do in the presence or absence of those conditions. I think these tests test but the mood of the examinees at the time of writing rather than their personality.
IF I COULD I WOULD.
If I could I would suggest that you give a multiple choice personality test to a group of participants. Do not reveal the test scores to them. After 30 minutes ask the same participants to write the same test. Compare each participant's score in the first and second tests as well as the answers to the same questions in both tests and see whether they will match.