87), in which Dr. Bruce P. Squires says "Language is so basic to our lives that we all assume we use it effectively." I suppose I am a lone voice, but as a pediatrician I find "pediatric pain" as offensive as "pediatric homicide". John U. Crichton, MB, ChB Professor emeritus Department of Paediatrics British Columbia's Children's Hospital Vancouver, BC
Reference 1. Crichton JU: In defense of pediatrics [C]. NEngl JMed 1 987; 316: 1219
[Touche.
-
Edi
Screening for congenital dislocation of the hip: an economic appraisal 1984, issue of CMAJ (130: 1149-1156) M. Jane Fulton and Morris L. Barer reported the results of an economic evaluation of screening for congenital dislocation of the hip (CDH). Using their assumptions and treatment costs one can show that they overestimated the cost of the screening strategy. Substituting the revised cost in their threshold analysis results in a change in the "cost advantage" regions in favour of the screening strategy. In Tables III and IV of the article the 1981-82 total cost of open reduction of the hip is given as $10 178.15; for closed hip reduction the figure is $8436.89. With the authors' estimate of 40% and 60% allocation between open and closed reduction respectively the weighted average of the two costs is $9133.40. When this estimate is applied to their assumed incidence rate of 1.5 cases of CDH per 1000 the treatment cost is correctly reported as $13 700 per 1000 infants unscreened. A problem arises, however, in n the May 1,
evaluating the costs of the screening option. The authors used $13 700 as the treatment cost per infant instead of $9133.40. If one applies this new figure to the treatment cost of 0.25 cases per 1000 (as in Table V of the article) the total cost of screening (with baseline assumptions) ranges from $4969 when the CDH incidence rate is 6/1000 to $6083 when the rate is 14.5/1000. Fulton and Barer therefore overestimated the screening costs by 23% and 19% respectively. I carried out a threshold analysis similar to that of Fulton and Barer in which two out of three variables in the cost equivalence equation were varied over a grid while the third variable was held constant. The variables considered were hospital per diem rate (PD), screening personnel cost per case (SPCC) and false-negative rate (FN). As a result of the analysis the "cost advantage" regions for screening expanded measurably, demonstrating that screening -in comparison to no screening - was more cost-effective than reported by Fulton and Barer. The expansion was much more pronounced when the false-negative rate was one of the variables considered in the sensitivity analysis. This is to be expected since the treatment cost of $13 700 per infant causes greater upward bias in their results at higher false-negative rates. The corrected estimate of $9133.40 per case, therefore, yields disproportionately greater gains as the false-negative rate rises. My estimates indicate that at an SPCC of $1.9 and a false-negative rate of 0.25/1000 the per diem hospital cost will have to decline to $50 (compared with the $65 reported by Fulton and Barer) for no screening to break even with screening. Similarly, at a per diem cost of $374 the break-even point would occur at an SPCC greater than $10. Furthermore, given an SPCC of $1.90 and a
hospital per diem cost of $374 screening has a clear cost advantage at false-negative rates well above 1/1000. At an SPCC of $4 the screening cost advantage declines to a false-negative rate of about 0.9/1000. Fulton and Barer's corresponding screening cost advantages at SPCCs of $1.9 and $4 are at the lower false-negative rates of 0.7/1000 and 0.5/1000 respectively. In conclusion, my analysis indicates that the cost of screening is at least 19% lower than Fulton and Barer reported. Furthermore, my threshold analysis shows that there are significant gains in the cost advantage of screening versus no screening beyond those reported earlier. Other things being equal, the size of those gains is positively related to the magnitude of the assumed false-negative rate. M.S. Marzouk, PhD Associate professor of economics York University North York, Ont.
Periodic health examination, 1990 update: 1. Early detection of hyperthyroidism and hypothyroidism in adults and screening of newborns for congenital hypothyroidism
[correction]
n page 958
O
of this article
(Can Med Assoc J 1990; 142: 955-961), by the Ca-
nadian Task Force on the Periodic Health Examination, the last sentence at the bottom of the first column should have read as follows, the corrected portion being in italics: "Careful assessment has shown that ostensibly asymptomatic patients with subclinical hypothyroidism in fact have symptoms, as compared with euthyroid control subjects." -Ed. CAN MED ASSoCIJ 1990; 143 (8)
711
Reference 1. Crichton JU: In defense of pediatrics [C]. NEngl JMed 1 987; 316: 1219
[Touche.
-
Edi
Screening for congenital dislocation of the hip: an economic appraisal 1984, issue of CMAJ (130: 1149-1156) M. Jane Fulton and Morris L. Barer reported the results of an economic evaluation of screening for congenital dislocation of the hip (CDH). Using their assumptions and treatment costs one can show that they overestimated the cost of the screening strategy. Substituting the revised cost in their threshold analysis results in a change in the "cost advantage" regions in favour of the screening strategy. In Tables III and IV of the article the 1981-82 total cost of open reduction of the hip is given as $10 178.15; for closed hip reduction the figure is $8436.89. With the authors' estimate of 40% and 60% allocation between open and closed reduction respectively the weighted average of the two costs is $9133.40. When this estimate is applied to their assumed incidence rate of 1.5 cases of CDH per 1000 the treatment cost is correctly reported as $13 700 per 1000 infants unscreened. A problem arises, however, in n the May 1,
evaluating the costs of the screening option. The authors used $13 700 as the treatment cost per infant instead of $9133.40. If one applies this new figure to the treatment cost of 0.25 cases per 1000 (as in Table V of the article) the total cost of screening (with baseline assumptions) ranges from $4969 when the CDH incidence rate is 6/1000 to $6083 when the rate is 14.5/1000. Fulton and Barer therefore overestimated the screening costs by 23% and 19% respectively. I carried out a threshold analysis similar to that of Fulton and Barer in which two out of three variables in the cost equivalence equation were varied over a grid while the third variable was held constant. The variables considered were hospital per diem rate (PD), screening personnel cost per case (SPCC) and false-negative rate (FN). As a result of the analysis the "cost advantage" regions for screening expanded measurably, demonstrating that screening -in comparison to no screening - was more cost-effective than reported by Fulton and Barer. The expansion was much more pronounced when the false-negative rate was one of the variables considered in the sensitivity analysis. This is to be expected since the treatment cost of $13 700 per infant causes greater upward bias in their results at higher false-negative rates. The corrected estimate of $9133.40 per case, therefore, yields disproportionately greater gains as the false-negative rate rises. My estimates indicate that at an SPCC of $1.9 and a false-negative rate of 0.25/1000 the per diem hospital cost will have to decline to $50 (compared with the $65 reported by Fulton and Barer) for no screening to break even with screening. Similarly, at a per diem cost of $374 the break-even point would occur at an SPCC greater than $10. Furthermore, given an SPCC of $1.90 and a
hospital per diem cost of $374 screening has a clear cost advantage at false-negative rates well above 1/1000. At an SPCC of $4 the screening cost advantage declines to a false-negative rate of about 0.9/1000. Fulton and Barer's corresponding screening cost advantages at SPCCs of $1.9 and $4 are at the lower false-negative rates of 0.7/1000 and 0.5/1000 respectively. In conclusion, my analysis indicates that the cost of screening is at least 19% lower than Fulton and Barer reported. Furthermore, my threshold analysis shows that there are significant gains in the cost advantage of screening versus no screening beyond those reported earlier. Other things being equal, the size of those gains is positively related to the magnitude of the assumed false-negative rate. M.S. Marzouk, PhD Associate professor of economics York University North York, Ont.
Periodic health examination, 1990 update: 1. Early detection of hyperthyroidism and hypothyroidism in adults and screening of newborns for congenital hypothyroidism
[correction]
n page 958
O
of this article
(Can Med Assoc J 1990; 142: 955-961), by the Ca-
nadian Task Force on the Periodic Health Examination, the last sentence at the bottom of the first column should have read as follows, the corrected portion being in italics: "Careful assessment has shown that ostensibly asymptomatic patients with subclinical hypothyroidism in fact have symptoms, as compared with euthyroid control subjects." -Ed. CAN MED ASSoCIJ 1990; 143 (8)
711
