The By-Band study: gastric bypass or adjustable gastric band surgery to treat morbid obesity: study protocol for a multi-centre randomised controlled trial with an internal pilot phase

Table 1 Data collection at the standard assessments

	Pre randomisation	Post randomisation
		Day of surgery	4 weeks	Months
		Day of surgery	4 weeks	3	6	12	24	36
Weight	X	X	X	X	X	X	X	X
Height	X
Blood pressure	X		X	X	X	X	X	X
Waist circumference	X		X	X	X	X	X	X
SF12	X		X		X	X	X	X
EQ-5D	X		X		X	X	X	X
IWQOL-Lite	X		X		X	X	X	X
GIQLI	X		X		X	X	X	X
HADS	X		X		X	X	X	X
Resource use questionnaires	X		X	X	X	X	X	X
Nutritional blood tests^c
Full blood count	X		X		X	X	X	X
Electrolytes	X		X		X	X	X	X
Creatinine	X		X		X	X	X	X
Fasting glucose	X		X		X	X	X	X
Lipids	X		X		X	X	X	X
HbA1c	X		X		X	X	X	X
Liver function tests	X		X		X	X	X	X
Iron, ferritin, vitamin B12	X		X		X	X	X	X
Folate/red cell folate	X		X		X	X	X	X
Lipid profile	X		X		X	X	X	X
25-hydroxyvitamin D	X		X		X	X	X	X
Calcium	X		X		X	X	X	X
Parathyroid hormone	X		X		X	X	X	X
Blood sample for future research	X							X
24-hour recall eating questionnaire	X			X	X	X	X	X
Binge eating questionnaire	X		X	X	X	X	X	X
Other co-morbidity
Sleep apnoea
STOP-BANG	X
Epworth sleepiness scale	X			X	X	X	X	X
Non-alcoholic fatty liver disease^b	X							X
National bariatric surgery registry			X		X	X	X	X
In-depth interviews^a	X		X	X	X	X	X	X

Table showing data and blood samples collected at different stages of the participant’s pathway through the trial (X = data or sample collected).
^aundertaken in a purposeful sample of participants.
^benhanced liver fibrosis test.
^cfor the assessment of co-morbidities.

ISSN: 1745-6215