1a) in 1998, a san diego reproductive clinic reported 42 live births to 157 women under the age of 38, but only 7 live births for 89 clients aged 38 and older. is this strong evidence of a difference in the effectiveness of the clinic's methods for older women? what type of study is this? *

1. The data given above is not a strong evidence of a difference in the effectiveness of the clinic method for older women. This is because, the data given in the question above gives a very low record of the number of birth for women that are 38 years old and older. 
2. The study above is an example of OBSERVATIONAL STUDY. An observational study is the type of study which draws inference from a sample and generalized it to a population. The study involves the observation of a certain set of individuals and the recording of specific outcomes. In this type of study, the researchers do not take steps to affect the outcomes of the study, that is, no treatment is given neither is any form of interference involved.