Table 1. Randomized clinical trials included in the meta-analyses: study characteristics.

Lead Author	Year	Calorie Restriction	Key Enrollment Criteria	Primary Endpoint(s)	Randomization	Outcomes Reported	Dropout	Study Power For Between Group Effect	Duration
Bradley	2009	500 kcal deficit per day in each group	BMI≥27	Insulin resistance (euglycemic-hyperinsulin-emic clamp)	Random number generator, blocked	Completers reported	Specifics not disclosed	Insulin Sensitivity	8 weeks
Brehm	2003	ad libitum LoCHO vs. calorie restricted LoFAT	BMI = 30–35	Weight and LDL	Specifics not disclosed	ITT with LOCF/BOCF with completers reported separately	Reasons listed	Specifics not disclosed	6 months
Brehm	2005	ad libitum LoCHO with ketosis vs. calorie restricted LoFAT	Women, BMI = 30–35	Resting energy expenditure	Randomization blocked, computer generated	Completers reported	Reasons listed	Specifics not disclosed	4 months
Brinkworth	2009	isocaloric with moderate energy restriction for both groups; Women~1429 & men~1667 kcal/d	Abdominal obesity + at least one risk factor for metabolic syndrome	Weight & Metabolic Effect	Specifics not disclosed	Completers reported	Reasons listed	Specifics not disclosed	1 year
Dansingera	2005	None	BMI = 27–42 + at least one risk factor for metabolic syndrome	Weight	Computer generated, stratified	ITT (LOCF) with completers reported separately	Reasons listed	Weight at Δ = 3% (or Δfrom baseline for each of 2%)	1 year
de Luis	2012	both calorie-restricted, ~1500kcal/day	BMI>30	Weight	Disclosed via envelope	All patients completed	All completed	Weight: power calculation stated differently in related publications	3 months
Flechter-Mors	2010	500 kcal deficit per day	metabolic syndrome, BMI = 27–45	Weight & body comp	Specifics not disclosed	Completers with ITT (LOCF) reported separately	Reasons listed	Specifics not disclosed	1 year
Fosterb	2003	caloric restriction in low fat group	obese	Weight	Random number generator	Actual data, not imputed	Specifics not disclosed	Specifics not disclosed	1 year
Fosterb	2010	caloric restriction in low fat group	BMI = 30–40	Weight	Random number generator	ITT reported (sensitivity analysis with completer data not significantly different)	Reasons listed	Weight at Δ = 3%	2 years
Gardnera	2007	no caloric restriction in Atkins or Ornish	women 25–50 yo, BMI = 27–40	Weight	Blocked, disclosed via envelopes	ITT (LOCF) reported (sensitivity analysis with completer data not significantly different)	Reasons listed	Weight at Δ = 2.7kg	1 year
Lean	1997	1200 kcal/day in each group	BMI≥25	Weight	Specifics not disclosed	ITT (LOCF) reported; also set deltas = 0 where no f/u data available	Specifics not disclosed	Specifics not disclosed	6 months
Lima	2010	1548 kcal/day in each group	BMI = 28–40	Weight & CV risk factors	Stratified	Modeled to use partial data, rather than ITT or LOCF	Reasons listed	Weight at Δ = 1kg	15 months
Meckling	2004	restriction in both LoFAT & LoCHO	BMI>25 with dietary intake of >4000 kJ/d	Weight, body comp & lipids	Specifics not disclosed	Appears to be completer results from text	Specifics not disclosed	Specifics not disclosed	10 weeks
Ruth	2013	500 kcal deficit target in each group	BMI 29–45	Weight loss, with focus on adipose tissue inflammation	Randomization blocked	Completers reported	Reasons listed	Specifics not disclosed	12 weeks
Trubya,b	2006	None	BMI = 27–40	Weight and body fat	Stratified	For weight ITT (LOCF) with lipids reported for completers	Reasons listed	Weight at Δ = 4kg	6 months
Volek	2009	not instructed to reduce calories in either group (both did)	BMI>25	Cardiovascular risk factors	Specifics not disclosed	All completed	All completed	Specifics not disclosed	12 weeks
Yancy	2004	LoFAT with caloric restriction	BMI = 30–60 & abnormal lipids	Weight & lipids	Computer generated	Missing data imputed	Reasons listed	Specifics not disclosed	6 months