Scientific principles and process

What are the stages of the scientific cycle ?

1-observation2-construction of a testable hypothesis3-experimental design4-gathering, recording and analysis of data5-evaluation of results and conclusions 6-formation of a revised hypothesis where necessary

What is validity ?

Variables controlled so that any measured effect is likely to be due to the independent variable

What is reliability ?

Consistent values in repeats and independent replicates

What is accuracy ?

Data or means of data sets are close to the true value

What is precision ?

Measured values are close to each other

What is a pilot study ?

It's a trial run of an experiment that's integral to the development of an investigation

Name 5 reasons for carrying out a pilot study

To plan procedures, asses validity and check techniques, allows for evaluation and modification of experimental design, ensures there's an appropriate range of values for the ID, allows investigator to establish number of repeat measurements required to give a representative value for each independent data point.

ID

what's changed

D

Being measured

Discrete and continuous variables

Discrete-variables are distinct and unrelated to each otherContinuous-range of values

Why control groups used ?

Provides evidence that any observed effect is likely due to the ID

Difference between simple and multifactorial experiments

Simple-one IDmultifactorial-combination of more than one ID or combination of treatments

What's an observational study ?

The ID isn't directly controlled by investigator for ethical or logical reasons, good at detecting correlation, but as don't directly test a hypothesis, less useful for determining causation.

What's a confounding variable ?

Other variables besides ID may affect D

Difference between negative and positive control

Negative-provides results in absence of a treatment Positive-

Whats in vitro and in Vivo ?

Vitro-technique of performing a given procedure in a controlled experiment outside a living organism Vivo-refers to experimentation using a whole, living organism

What's difference between qualitative, quantitative and ranked data ?

Quantitative-subjective and descriptive Qualitative-measurable, usually with a numerical valueRanked-numerical values are replaced by rank and then sorted