User Manual: Inquisit Leeds Food Preference Questionnaire (LFPQ)


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								*Leeds Food Preference Questionnaire (LFPQ)*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-08-2021
last updated:  07-27-2023 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 07-27-2023 Millisecond Software

Millisecond Software thanks Dr. Graham Finlayson for his collaboration on this script!

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BACKGROUND INFO 	
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This script implements the Leeds Food Preference Questionnaire (LFPQ), a computer-based procedure to measure 
explicit and implicit food preferences.

The original e-prime script is available at:
https://licensing.leeds.ac.uk/product/leeds-food-preference-questionnaire-lfpq

Reference
Finlayson, G., King, N., & Blundell, J. (2008), The role of implicit wanting in relation to explicit 
liking and wanting for food: implications for appetite control, Appetite, 50(1), 120-127

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TASK DESCRIPTION	
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Participants are presented with an array of pictures of sweet and savory food items high and low in fat.

They work on 2 different tasks:
- explicit (FPQ): participants liking and wanting states are assessed as VAS ratings (scale: 0-100)
- implicit (FCQ): participants preferences are assessed via a forced-choice task with choices and choiceRTs

The two tasks are run in random order.

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DURATION 
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the default set-up of the script takes appr. 10 minutes to complete
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DATA OUTPUT DICTIONARY
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The fields in the data files are:

(1) Raw data file: 'lfpq_raw*.iqdat' (a separate file for each participant)*

build:						The specific Inquisit version used (the 'build') that was run
computer.platform:			the platform the script was run on (win/mac/ios/android)
date, time: 				date and time script was run 
subject, group: 			with the current subject/groupnumber
session:					with the current session id

blockCode, blockNum:		the name and number of the current block (built-in Inquisit variable)
trialCode, trialNum: 		the name and number of the currently recorded trial (built-in Inquisit variable)
								Note: trialNum is a built-in Inquisit variable; it counts all trials run; even those
								that do not store data to the data file. 
										
taskPresentationOrder:		the order in which (FPQ_L, FPQ_W) and FCQ tasks are run
phase:						ApVAS_pre, instructions, practice, test, ApVAS_post 

procedure: 					'fpq practice', 'fcq practice', from e-prime script: 'fpqL01', 'fpqW01', 'fcq001'
				
condition:					FPQ: the condition of the image presented (hfsa, hfsw, lfsa, lfsw)	
							FCQ: the conditions of the image pairs presented (Example: lfswlfsa)
									
							hfsa => high fat savory; 
							lfsa => low fat savory; 
							hfsw => high fat sweet;
							lfsw => low fat sweet
									

order:						each image has a particular index number, order refers to this index number
 
fpqImage:					the particular image shown in the current FPQ condition
fcqImageLeft:				the particular left image shown in the current FCQ condition 
fcqImageRight:			the particular right image shown in the current FCQ condition 

response (built-in variable):		FPQ: simply shows 'customslider' (= participant pressed somewhere on the slider) 
									FCQ: stores the scancode of the pressed response key => 32 = D (left); 36 = J (right)

taskResponse:				FPQ: stores the VAS value (0-100) selected
							FCQ: stores the selected image condition

latency (built-in variable):		the response latency (in ms); measured from onset of images
							

(2) Summary data file: 'lfpq_summary*.iqdat' (a separate file for each participant)*

inquisit.version:				Inquisit version run
computer.platform:				the platform the script was run on (win/mac/ios/android)
startDate:						date script was run
startTime:						time script was started
subjectId:						assigned subject id number
groupId:						assigned group id number
sessionId:						assigned session id number
elapsedTime:					time it took to run script (in ms); measured from onset to offset of script
completed:						0 = script was not completed (prematurely aborted); 
								1 = script was completed (all conditions run)
									
taskPresentationOrder:			the order in which (FPQ_L, FPQ_W) and FCQ tasks were run

//ApVAS ratings:
hungryApVASPre:				pre-rating (0-100) for ApVAS 'HungryNow' 
fullApVASPre:					pre-rating (0-100) for ApVAS 'FullNow' 
urgeApVASPre:					pre-rating (0-100) for ApVAS 'UrgeNow'

hungryApVASPost:				post-rating (0-100) for ApVAS 'HungryNow'
fullApVASPost:				post-rating (0-100) for ApVAS 'FullNow'
urgeApVASPost:				post-rating (0-100) for ApVAS 'UrgeNow'


//FPQ (explicit):
fpqLMeanRatingHFSA:		mean FPQ Liking rating (0-100) for HFSA (high fat savory items) 
fpqLMeanRatingHFSW:		mean FPQ Liking rating (0-100) for HFSW (high fat sweet items) 
fpqLMeanRatingLFSA:		mean FPQ Liking rating (0-100) for LHFSA (low fat savory items) 
fpqLMeanRatingLFSW:		mean FPQ Liking rating (0-100) for LFSW (low fat sweet items) 

fpqWMeanRatingHFSA:		mean FPQ Wanting rating (0-100) for HFSA (high fat savory items) 
fpqWMeanRatingHFSW:		mean FPQ Wanting rating (0-100) for HFSW (high fat sweet items) 
fpqWMeanRatingLFSA:		mean FPQ Wanting rating (0-100) for LHFSA (low fat savory items) 
fpqWMeanRatingLFSW:		mean FPQ Wanting rating (0-100) for LFSW (low fat sweet items) 

//FCQ (implicit):
fcqCountHFSA:				number of times HFSA  (high fat savory items) were chosen during the FCQ task 
fcqPropHFSA:				proportion of times HFSA items were chosen if they were presented 
fcqMeanChoiceRTHFSA:		mean choice reaction time to choose HFSA items
(same for HFSW, LFSA, LFSW items)
							
							
* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions
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EXPERIMENTAL SET-UP 
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Modules:

1. Start: 1 slide

2. ApVASProc_pre: 3 VAS questions (sequential selection)
	- hungry now
	- urge now
	- full now

3. Main Menu: includes optional instruction block, optional practice session and the test session
- gives the option to run an instruction block
- gives the option to run the practice session as stand-alone session (order of tasks to practice can be selected; practice blocks can be skipped)
	- practice blocks run 4 practice trials per each task (QPF, QCF)
- test session: (mandatory)
	- test randomizes the order of the FPQ and FCQ tasks
	 - FPQ: separated into two blocks FPQ_l and FPQ_w; each of them run 16 trials (order randomized); a rest block is run in between the two runs
	 - FCQ: 96 trials, separated into 3 runs (rest blocks in between)
	 - both tasks start with the 4 practice trials (the same as run in the stand-alone practice session)

4. ApVASProc_post: 3 VAS questions (sequential selection)
	- hungry now
	- urge now
	- full now

5. End: 1 slide

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STIMULI
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The food stimuli run are provided  with the original e-prime script.
https://licensing.leeds.ac.uk/product/leeds-food-preference-questionnaire-lfpq

HFSA => high fat savory; 
LFSA => low fat savory; 
HFSW => high fat sweet;
LFSW => low fat sweet

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INSTRUCTIONS 
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The instructions run are provided with the original e-prime script.
https://licensing.leeds.ac.uk/product/leeds-food-preference-questionnaire-lfpq

Notes: 
* the instructions were translated into English from the French instructions by K.Borchert for 
Millisecond Software.
Task instructions were taken from Finlayson et al(2008).

* if the current script is run on touchscreens (with no mouse), the instructions adapt.
This was not part of the original program