When conducting a experiment does the number of trials affect the results?

The number of trials does not affect the result as each individual trial or experiment yields its own result caused by random small variations in the techniques used. What is affected is the conclusion derived from pooling all the individual results for the same type of trial and analysing the value obtained by statistical methods. It is generally reckoned that at least seven trials are required for the purpose of statistics and the analysis is commonly expressed as the Mean (average value) and Standard Deviation, (a number that reflects the extent of the variation between the individual trials). However, different statistical methods are used for analysing different types of data, the commonest reflecting the difference between parametric (the variation is the same on both sides of the mean) and non-parametric (The spread of variation is greater on one side of the mean than the other). Obviously a considerable number of individual trials is required to be able to make a valid distinction between the two.