experimental study design

Question 1

clinical trials

Answer 1

involve a human or more, not observational instead require a manipulating intervention

Question 2

NIH clinical trial criteria

Answer 2

1. involves human participants, 2. prospectively assigns participants an intervention, 3. evaluates an interventions effect, 4. measures health related biomedical or behavioral outcome

Question 3

phases of clinical trials

Answer 3

preclinical: lab studies on cells and animals
phase I: small scale, a focus on safety and limiting dose toxicity
phase II: medium scale, tests efficacy and safety
phase III: large scale, randomized trials comparing standard treatment (necessary for FDA approval)
phase IV: post approval, monitoring for safety and side effects

Question 4

randomization

Answer 4

eliminates selection bias and ensures comparability between groups

Question 5

blinding

Answer 5

can be single or double, prevents bias in treatments expectations and assessments

Question 6

SMART trials

Answer 6

modify interventions based on interim results

Question 7

crossover designs

Answer 7

participants switch interventions after a washout period

Question 8

adaptive randomization

Answer 8

adjusting treatment assignment based on early data

Question 9

type I error

Answer 9

false positive - claims treatment worked when it did not

Question 10

generalizability

Answer 10

ensuring results apply beyond study population

Question 10

type II error

Answer 10

false negative - fails to detect a real effect

Question 11

volunteer bias

Answer 11

participants may not represent the general population

Question 12

complex logistics

Answer 12

recruitment, compliance and cost challenges