I am struggling with how to approach my dataset for a meaningful analysis and need help.
I am looking at wound healing of sharks over time and have hit a wall with analysis. My data consist of injury cases which are tracked over time. Injury healing is measured as percentage wound area/perimeter change since initial sighting. Each case varies in the number of days since initial sighting and the total number of sightings with some only seen twice and some seen 5 times.
I want to look at changes over time and be able to statistically say that over time the wounds are decreasing in size. How can I achieve this? Should I use repeated measures?
Here is an example of data:
Please tell me if this does not make sense or if more information is required to clarify my question.