Variables
In research, variables are elements that can be manipulated, measured, or controlled. Understanding them is crucial for any study. Here's a simple breakdown of two fundamental types of variables:
- Independent Variable (also known as Controlled or Manipulated Variable): This is the variable that you, the researcher, will change or manipulate. It's called "independent" because its variation is not dependent on other variables in your experiment.
- For example, if you're studying the effects of sunlight on plant growth, the amount of sunlight would be your independent variable.
- Dependent Variable (also known as Responding Variable): This is the variable that you measure in the experiment. It's called "dependent" because it depends on the changes you make to the independent variable.
- Continuing with the plant growth example, the height of the plant would be the dependent variable, as it could change based on the amount of sunlight received.
In a research statement, the independent variable typically comes before the dependent variable.
- For example, you might say: "This study examines how the amount of sunlight (independent variable) affects plant growth (dependent variable)." This helps clarify the cause-and-effect relationship you're investigating.
Here are some examples of independent and dependent variables in research related to Speech-Language Pathology (SLP):
Example 1: Stuttering Therapy
- Independent Variable: Type of therapy used, e.g., [FLUENCY SHAPING OR STUTTERING MODIFICATION])
- Dependent Variable: Frequency of stuttering events during conversation, e.g., [FREQUENCY OR RATE AND STUTTERING EVENTS]
Example 2: Aphasia Rehabilitation
- Independent Variable: Types of rehabilitation exercises (e.g., word retrieval exercises, picture naming)
- Dependent Variable: Improvement in language skills, measured using a standardized language assessment
Develop your Keyword Search Around your main topic, then the Independent and Dependent Variables:
For example:
1. Main topic:
Aphasia
2. Independent Variable(s):
("picture naming" OR "semantic mapping")
3. POSSIBLEY HELPFUL: Include terms to describe your Dependent Variable:
("Improvement in language skills" OR "language assessment" OR "language skills measurement" OR "standardized language assessment")
4. Put it all together:
(Aphasia) AND (picture naming" OR semantic mapping) AND ("Improvement in language skills" OR "language assessment" OR "language skills measurement" OR "standardized language assessment")
Example 3: Early Language Development
- Independent Variable: Age of exposure to a second language (e.g., before age 3, between ages 4-6, etc.)
- Dependent Variable: Proficiency in second language skills, such as vocabulary size or grammatical accuracy
Example 4: Hearing Aids and Speech Comprehension
- Independent Variable: Use of hearing aids (e.g., with or without hearing aids)
- Dependent Variable: Speech comprehension scores in noisy environments
Example 5: Speech Sound Disorders in Children
- Independent Variable: Intervention approach (e.g., traditional articulation therapy, phonological process therapy)
- Dependent Variable: Number of speech sound errors made in conversation
Example 6: Telepractice vs. In-Person Therapy
- Independent Variable: Mode of therapy delivery (e.g., telepractice or in-person)
- Dependent Variable: Client satisfaction rates or treatment outcomes
