So there’s 100 residents, and the prevalence after 2 years is =10 at the beginning, +5 in the first year, +10 second year, and -3 that healed, for a total prevalence of 22 residents or 22/100=22 percent. Thus, prevalence = above the standard. For incidence, it’s 15 new cases out of 90 residents over the 2 years (100 total residents – 10 that already had ulcers), or 15 new ulcers per 180 patient⋅years. This would be 83.3 new ulcers per 1000 patient⋅years if you extrapolated it out -- basically (1000/180) * 15 -- thus, incidence = above the standard.
zelderonmorningstarOkay I feel like an idiot cause I thought: Above the Standard = Doing a good job keeping old people from getting ulcers. Thumbs up. Below the Standard = I wouldn’t let my worst enemy into your ulcer ridden elder abuse shack.+232019-05-24T13:06:46Z
aladar50@zelderon Ohh damn. I could totally see how one could view the answer choices that way. I think it is important to read how they are phrased - they are asking if the center is above THE standard or below THE standard. The “standard” is an arbitrary set point, and the results of the study are either above or below that cut off. Maybe if it was “above/below standards” that would work. Also, being above the standard could either be a good thing or bad thing. If say you were talking about qualifying for a competition and you have to do 50 push ups in a minute, then being above=good and below=bad. In this case, having more ulcers than the standard = bad.+12019-05-24T13:15:30Z
saynomore@aladar Thank you!!! but how did you get the 15 new ulcers per 180 patient⋅years? I mean I understand the 15 part, but not the second part ... hence why I messed this up, lol :|+22019-05-24T13:19:41Z
aladar50@saysomore Because the study is looking at 100 residents over a period of 2 years. Since 10 already had the disease at the start, when looking at incidence you only include the subjects that have /the potential/ of developing the disease, so 90 patients over 2 years. This would be 90 patient⋅years per year, or a total of 180 patient⋅years over the course of the study.+72019-05-24T13:21:14Z
sympathetikey@zelderonmorningstar I thought the same exact thing. Had the right logic, but then just put the backwards answer. +22019-06-04T22:36:45Z
kaiI wonder if they chose this wording on purpose just to fuck with us or if this was accidental. My guess is there's some evil doctor twirling his thumbs somewhere thinking you guys are below the standard.+122019-07-10T23:26:53Z
symptomatologyGot it wrong!messed up in understanding options,
Btw, 15/90 is somewhat 16 percent and their standerd is 50/1000 5 percent!.. this is how i knew that incidance is way up! +2020-01-21T13:55:12Z
donttrustmyanswersPatients with an ulcer are not immune to getting new ulcers --> You should include all patients at risk. But either way, the answer is the same as long as you can read NBME speak. +2020-02-16T23:28:14Z
to snoo-finity ... and beyond!
submitted by aladar50(32), 2019-05-24T13:04:46Z
So there’s 100 residents, and the prevalence after 2 years is =10 at the beginning, +5 in the first year, +10 second year, and -3 that healed, for a total prevalence of 22 residents or 22/100=22 percent. Thus, prevalence = above the standard. For incidence, it’s 15 new cases out of 90 residents over the 2 years (100 total residents – 10 that already had ulcers), or 15 new ulcers per 180 patient⋅years. This would be 83.3 new ulcers per 1000 patient⋅years if you extrapolated it out -- basically (1000/180) * 15 -- thus, incidence = above the standard.