Response keyboard missing in results (in a anesthetist monitoring test)

maxime

Hello everyone,

A nurse anesthetist and me develop an attention test in Opensesam in ordrer to measure impact of smartphone use in operation room.
In practice, participants see a cardiac monitor with blood pressure values and oxgen saturation values changing and, at the same time, hear heartbeat sounds.

Participants have to press some keyboard keys as soon as possible :

• When they hear a slow down or a acceleration of the heartbeat sound;
• When they saw a oxygen saturation number is under 90/65 or superior than 125/90

• When they saw a blood pressure number under 90
  The goal is to measure the performance with the number of good keypress and the reaction time of these responses. With one key for each variable (for ex : ‘a’ for heartbeat, ‘z’ for saturation and ‘d’ for blood pressure).
  But we have two issues :

• First, the duration of the whole test is twice the time expected. I have read chapters of time issues in Opensesame in the website but I still don’t understand the problem clearly. Moeover, it’s not so important because we have developed the test taking into account this duration problem.

• Second and worst, when I look at the table results of a participant, some hits on the keyboard (link to stimulation) are missing (see in “response” column). So, it’s impossible to have the score at the test and the reaction time.

I don’t know how to write in Python code, so I only use the interface of Opensesame (which I like very much by the way, thanks for your work Sebastiaan Mathôt !). Can someone help me for this ? What am I doing wrong ? Why some hits on keyboard are not recorded ?

My nurse anesthetist colleague want to start the testing next week. What can I do ???

I leave a sample of the test, if someone want to look at it…

Thanks very much for your help.

eduard

Hi Maxime,

Sorry for the delay. I hope it will still be useful to you...

First, the duration of the whole test is twice the time expected.

That is weird. Your experiment is very simple and I don't see where very long delays should originate from. One thing that you can do is set the sound field in the sampler to 0. Otherwise the experiment doesn't proceed while the sound is playing (If it is 0, you still here the sound, but at the same time you are already waiting for a keyboard response) How long does it take? Given a little overhead here and there, it shouldn't take longer than a minute, right?

Second and worst, when I look at the table results of a participant, some hits on the keyboard (link to stimulation) are missing (see in “response” column). So, it’s impossible to have the score at the test and the reaction time.

You allow participants only 500ms to respond. That is really not much. The problem is that if participants need longer, then all their key presses won't be recorded anymore. In that case, you should consider this a miss trial. So, I recommend increasing the timeout to 1second or so. And post-select slow responses during the analysis if you need to.

Eduard