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Record W2168031236 · doi:10.1503/cmaj.045019

Effects of making emergency contraception available without a physician's prescription: a population-based study

2005· article· en· W2168031236 on OpenAlexvenueno aff
Judith A. Soon

Bibliographic record

VenueCanadian Medical Association Journal · 2005
Typearticle
Languageen
FieldMedicine
TopicReproductive Health and Contraception
Canadian institutionsnot available
Fundersnot available
KeywordsEmergency contraceptionMedical prescriptionMedicineFamily planningLevonorgestrelFamily medicineConfidence intervalPopulationPharmacyPediatricsMedical emergencyEmergency medicineEnvironmental healthNursingInternal medicine

Abstract

fetched live from OpenAlex

BACKGROUND: Timely access to emergency contraception has the potential to reduce the number of unwanted pregnancies and subsequent abortions. A public health policy initiative in British Columbia beginning in December 2000 allowed pharmacists to provide emergency contraceptives (ECs) without a prescription. We sought to determine changes in EC use after the policy was introduced and to analyze EC use with data generated by the policy. METHODS: All Ovral, Preven and Plan B EC prescriptions from Jan. 1, 1996, to Dec. 31, 2003, were identified through the BC PharmaNet and Medical Services Plan administrative databases and the data analyzed to determine changes between 1996 and 2002. Changes over time were determined in the frequency of EC provision, choice of EC agent, frequency of EC use by age group, repeat use and geographic distribution of EC prescription for the pre- and post-policy periods. Anonymized patient-specific data from treatment consent forms were used to describe the reason for EC use, interval between unprotected intercourse and EC prescription, proportion prescribed for immediate or future use, referrals for regular birth control and STD screening and concomitant antiemetic use. Consent data also provided the time in the menstrual cycle that the EC was requested. RESULTS: The number of EC prescriptions increased from a pre-policy mean of 8805 (99% confidence interval 7823-9787) in the years 1996 to 2000 to a post-policy total in 2002 of 17 794. Physicians prescribed the levonorgestrel regimen (Plan B) less frequently than did pharmacists. The frequency of EC use was highest among women aged 20-24 years across all study years, and all age groups demonstrated a post-policy increase in use. On average, 2.1% of the women received an EC 3 or more times a year over the period of the study. More women in urban regions received ECs than women in more rural areas of the province. Analysis of pharmacist treatment consent forms used in 2001 and 2002 showed that 56.2% of women receiving an EC reported using a method of birth control that had failed, 55.7% of pharmacist-provided ECs were obtained within 24 hours after unprotected intercourse, 1.1% of ECs were obtained for future use, antiemetics were provided to 57.7% of women receiving the Yuzpe regimen (Ovral, Preven) and to 20.5% of women receiving levonorgestrel, and women tended to seek ECs when unprotected intercourse occurred at the time of highest risk of pregnancy in their menstrual cycle. Women in greatest financial need obtained ECs more frequently from physicians than from pharmacists. INTERPRETATION: The policy change that granted pharmacists authority to provide ECs to women without a physician's prescription did not simply expand EC availability but was associated with an overall increase in EC use in the province.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.006
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.014
Threshold uncertainty score0.027

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.006
Meta-epidemiology (narrow)0.0000.001
Meta-epidemiology (broad)0.0000.001
Bibliometrics0.0010.002
Science and technology studies0.0010.001
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0010.002
Insufficient payload (model declined to judge)0.0040.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.010
GPT teacher head0.283
Teacher spread0.272 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations70
Published2005
Admission routes1
Has abstractyes

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