title: Sampling size in the verification of manufactured-supplied air kerma strengths.
abstract: Quality control mandate that the air kerma strengths (S(K)) of permanent seeds be verified, this is usually done by statistics inferred from 10% of the seeds. The goal of this paper is to proposed a new sampling method in which the number of seeds to be measured will be set beforehand according to an a priori statistical level of uncertainty. The results are based on the assumption that the S(K) has a normal distribution. To demonstrate this, the S(K) of each of the seeds measured was corrected to ensure that the average S(K) of its sample remained the same. In this process 2030 results were collected and analyzed using a normal plot. In our opinion, the number of seeds sampled should be determined beforehand according to an a priori level of statistical uncertainty.
authors.affiliation: Department of Oncology, Clínica Universitaria de Navarra, University of Navarra, Avda Pío XII s/n, Pamplona, Navarre, Spain. liramos@unav.es
authors.forename: Luis Isaac
authors.initials: LI
authors.lastname: Ramos
authors.forename: Rafael
authors.initials: R
authors.lastname: Martinez Monge
mesh_terms: D000388:Air; D001918:Brachytherapy / Q000295:instrumentation*; D002138:Calibration; D006801:Humans; D015233:Models, Statistical; D016011:Normal Distribution; D011336:Probability; D011786:Quality Control; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D015203:Reproducibility of Results; D018401:Sample Size