The spelling of hypothesis when written as "hypotheses" indicate plural. The hypothesis is a statement or declaration of the expected outcome of a research study. Often it is called as an educated guess or hunch that the researcher proposes for testing. It is based on logical-rationale and has empirical possibilities for its testing, i.e. using statistical methods. Hypothesis provides a statement about a specific relationship to be tested. Refer to Example 12 which is a statement showing the researcher's hunch on the relationship between breathing exercises and post-operative respiratory complications in patients undergoing surgery.
Normally, in an hypothesis there are four elements: (i) dependent and independent variables, (ii) some type of relationship between independent and dependent variable, (iii) the direction of change, i.e. stating "more or less", "higher or lower" increased or decreased, and (iv) it mentions the subject, i.e. the population being studied. Can you identify these elements in the' exercise (Activity 6) given at the end of this unit. The type of variables here, seem to have a cause and effect relationship, i.e. the exercise is the cause and the effect is the reduction of respiratory complications. We cannot absolutely assure this. Remember those innumerable variables, some of which are shown in Example 1. These other variables may also influence reduction of complications. In nursing studies it is difficult to control all variables as the subjects and the researchers are also human being and are all-different. You may appreciate that patients, doctors, nurses are heterogeneous in nature and it is difficult to control human qualities.