Extended release opioid, individualized total daily dose, dosing interval is every 12 hours

Lactose pill manufactured to mimic extended release opioid formulation

An inventory of questions about pain, including a pain diagram, pain intensity rating subscales and pain interference rating subscales. The four pain intensity rating subscales are "pain at worst", "pain at least", "pain on average" and "pain right now". These are 10-point scales with a minimum of "0" =no pain, and a maximum of "10"= pain as bad as you can imagine", where higher scores are worse. Pain intensity subscales can be combined as an average on the same scale of 0-10. The eight pain interference subscales measuring interference on general activity, mood, walking ability, work, relations with other people, sleep, enjoyment of life, are 10-point subscales which range a minimum of "0" = pain does not interfere, to a maximum of "10"=pain completely interferes with the item. Higher scores are worse outcomes. Pain interference subscales may be combined as an total score out of 80, or divided by eight to get an average of pain interference on the scale of 0-10.

A self-administered scale for grading 16 opioid withdrawal symptoms on a scale of '0' meaning 'not at all' to '4' meaning 'extremely'. Higher numbers are worse outcomes.

The short version of the ARCI is a well-validated, standardized, self-report questionnaire of 49 "true-false" items and is used to differentiate subjective effects of drugs. True = 1, False = 0, responses to selected items are added for scores on different scales. Three of the scales are pertinent to opioid abuse liability: MBG (morphine-benzedrine group), a measure of euphoria, minimum = 0, and a maximum = 16); PCAG (pentobarbital-chlorpromazine-alcohol group) a measure of sedation, minimum =0, maximum=15; LSD (lysergic acid diethylamide scale) a measure of dysphoric and psychotomimetic changes, minimum=0, maximum =14. Higher scores are worse outcomes.

A widely used, self-reported questionnaire for assessing drug-induced changes in mood. It has 72 adjectives and phrases describing feelings people have, and ask for the user to describe "how you are feeling right now" on a 5 point scale of descriptives: with a minimum value = 0 "Not at all", to a maximum value of 4= "extremely". Total mood disturbance is calculated by adding the results of the 6 subscales, and then subtracting the vigor -activity subscale (range 0-200). Subscales (six) are calculating by adding specific items: tension-anxiety (9 items, range 0-36), depression (15 items, range 0-60), anger-hostility (12 items, range 0-48), vigor-activity (8 items, range 0-32), fatigue (7 items, range 0-28), confusion-bewilderment (7 items, range 0-28).

Visual analog scales are 100mm lines, anchored at the ends by opposing adjectives (e.g. like-dislike). "Like" is at the minimum, 0mm mark, "dislike" is at the maximum, 100mm mark. Subjects are instructed to rate how they feel along a continuum by making a mark along the line. The measurement of drug liking is considered to be one of the most sensitive and reliable assessments of the likelihood of abuse of a drug. "Liking" and "High" at the 100mm marks would be considered worse outcomes in terms of likelihood of abuse of a substance.

Serum opioid concentrations at 0,30 mins, 1,2,3,4,5,6 hours post-dose

The maximum concentration achieved post dose

Time that peak plasma concentration occurs post-dose

Calculated area under the plasma concentration versus time curve, which describes exposure to the drug.

The peak plasma concentration (Cmax) divided by the time to peak plasma concentration, which describes a calculation of the average rate of increase in plasma concentration over the interval between treatment administration and the time of peak plasma concentration.