A company is testing a new weight-loss supplement. For the study, the company enrolled 189 obese or overweight middle-aged people who agreed to take a weight-loss supplement for eight weeks. Half took the supplements and half took a placebo. A representative portion of their results is shown in the table below. What conclusions can you draw from this portion of the results?

SUBJECT #

GROUP

BASELINE WEIGHT

8 WK WEIGHT LOSS/GAIN

26

placebo

192

+2.7

32

supplement

151

-3.2

35

supplement

204

-6.6

54

supplement

216

-4.9

85

placebo

185

-2.4

116

supplement

197

+3.4

133

placebo

290

+6.8

147

supplement

235

-9.0

153

placebo

188

+5.8

167

supplement

233

-5.3

188

supplement

198

-7.3

The supplement seems to be effective, but more trials are necessary.
The supplement is not effective because some of the people gained weight.
The supplement is no more effective for causing weight loss than the placebo.
The supplement produced results that are identical to the placebo.