Table 3

Reliability of current smoking assessment tools

QuestionResponse choicesComplete observationsPearson’s r or agreement
Which of the following categories best captures the amount of marijuana you smoked over the past 30 days?An eighth of an ounce (which is the same as 3.5 g)92Pearson’s r=0.83
A quarter of an ounce (which is the same as 7 g)
A half of an ounce (which is the same as 14 g)
Three quarters of an ounce (which is the same as 21 g)
An ounce (which is the same as 28 g)
Grams
Ounces
Hits
Other
Refused
Don’t know
In the last 30 days have you smoked a …Joint97Agreement=77.3%
Pipe
Bong
Blunt
Spliff
In the last 30 days, how many days per week did you smoke a joint?Every day53Pearson’s r=0.63
6 days/week
5 days/week
4 days/week
3 days/week
2 days/week
1 days/week
Days/month
Refused
Don’t know
On those days, how many joints did you smoke?___ Number of joints53Pearson’s r=0.92
Less than one joint
Refused
Don’t know
In the last 30 days, how many days per week did you smoke a pipe?Every day55Pearson’s r=0.77
6 days/week
5 days/week
4 days/week
3 days/week
2 days/week
1 days/week
Days/month
Refused
Don’t know
On those days, how many pipes did you smoke?___ Number of pipes51Pearson’s r=0.63
Less than one pipe
Refused
Don’t know
In the last 30 days, how many days per week did you smoke a bong?Every day9Pearson’s r=0.76
6 days/week
5 days/week
4 days/week
3 days/week
2 days/week
1 days/week
Days/month
Refused
Don’t know
On those days, how many bongs did you smoke?___ Number of bongs9Pearson’s r=0.85
Less than one bong
Refused
Don’t know
Number of days marijuana was smoked in past 30 days*Pearson’s r=0.78*
Total number of joints/pipes/bongs used in past 30 days*Pearson’s r=0.89*
  • *Calculated based on previous questions.