Racial and Ethnic Disparities in Acute Pain Control

The study was conducted at two urban academic Emergency Departments associated with
Montefiore Medical Center. Emergency Medicine residents and full-time Emergency Medicine
faculty are present at both sites. One of the sites is a municipal hospital Level 1 Trauma
Center managing approximately 50,000 adult patients per year. The other site is the primary
academic medical center, managing approximately 80,000 adult patients per year, many of them
requiring tertiary care. Both departments serve an urban population that is predominantly
African-American and Hispanic.

Study Protocol Data were obtained from a convenience sample of patients from September, 2003
through November, 2006. Patients were eligible if the provider suspected an isolated
long-bone fracture and long-bone films were obtained. Because it was not possible to
determine which patients would have positive films in advance, all patients with suspected
fractures who met other inclusion criteria were initially considered eligible and enrolled.
Only those with confirmed fractures were included in the final study sample. Patients were
considered to have fractures if the radiology report by an attending radiologist specified
an isolated long-bone fracture defined as a fracture of the humerus, radius, ulna, femur,
tibia, or fibula (ICD-9 codes: 812, 813, 821, 823, and 824).

Data collection took place from 8:00 am to midnight seven days a week at one institution and
24 hours a day, seven days a week at the other. Data were collected on a standardized data
collection instrument by trained fluently bilingual (Spanish and English) Research
Associates. The Research Associates attended a three-day course in research ethics, and
specific data collection procedures of the study. This was followed by a two-week internship
during which new Research Associates were paired with more experienced Research Associates.

Research Associates approached patients whose triage note indicated an extremity injury,
extremity pain, if the Research Associate observed a physical indication of extremity
injury, or if a provider identified a patient who was potentially eligible for the study.
Eligible patients were asked to sign informed consent. Data were collected from patients at
the time of the physician's examination of the patient (baseline) and at discharge. At
discharge the treating physician was asked to rate the patient's pain when he/she first
examined the patient. If the physician's shift ended before the patient was discharged
he/she was asked to rate the patient's initial pain before leaving the ED.

Measurements The names of all medications, dose, route, and time administered were obtained
in real time from the chart and ED staff. Patients were categorized as receiving: 1) no
analgesics; 2) NSAIDS or acetaminophen; or 3) opioids. If both NSAIDS or acetaminophen and
opioids were administered, patients were categorized as having received opioids. Analgesics
given solely for fracture reduction were not used to categorize patients. Opioid analgesics
were transformed into morphine equivalents as follows: 1 mg morphine = 3 mg of oxycodone;
0.15 mg of hydromorphone, and 13 mg of codeine. No other opioid analgesics were used with
the exception of fentanyl, which was only used for fracture reduction.

The primary predictor variable was self-reported race/ethnicity of the patient. This was
measured by the response to the question: "Do you consider yourself to be: Hispanic/Latino,
White/Caucasian, Black/African-American, multi-racial, or other?"

Covariates: Patients' pain and provider assessment of patients' pain are determinants of
treatment and thus have the potential of confounding the relationship between race/ethnicity
and treatment if they vary systematically by race/ethnicity.10 Pain was measured in several
ways: Patients were asked to rate their pain intensity on a validated and reproducible
11-point numerical rating scale (NRS) ranging from 0 "no pain", to 10 "worst imaginable
pain".18 They were also asked to describe pain categorically as: "no pain", "mild pain",
"moderate pain", or "severe pain". Change in pain was measured by response to the question:
"How does your pain feel now compared to when you entered the Emergency Room?" It was also
measured by the difference between the patient's rating of pain at entry and pain at
discharge. At time of discharge the treating physicians were asked to recall and rate the
patient's initial pain using the same verbal descriptors used by the patients We reasoned
that asking doctors to rate patients' pain before they made treatment decisions might bias
treatment.

Other clinically plausible confounders of the relationship between pain management and
race/ethnicity include: sex, age, educational level (some high school, high school or
General Equivalency Diploma (GED), some college, Bachelor's degree or higher), insurance
status (self-pay, health maintenance organization (HMO) or private insurance, Medicaid,
other insurance), accompanied to the ED by someone who might act as a patient advocate,
mechanism of injury (fall, sports, motor vehicle, other), fracture reduction in ED, and
arrival by ambulance.

Data Analysis:

Patient characteristics are reported as means with standard deviations, medians with
interquartile ranges (IQR) and percentages. We used chi-square tests to compare discrete
patient characteristic by race/ethnicity. One-way analysis of variance was used to compare
continuous characteristics and the Kruskal-Wallis test to compare medians of non-normally
distributed variables.

Logistic models were used to test for the presence of an independent (adjusted) association
between race/ethnicity and the treatment of pain. We used forced entry into the model of
initial patient rating of pain intensity, provider rating of patient's pain at baseline,
hospital, sex, age, education, insurance status, whether accompanied to the ED, mechanism of
injury, fracture reduction in ED, and arrival by ambulance. Hosmer Lemeshow's test was used
to assess model fit. We used Zhang and Kai's method for estimating relative risks from the
odds ratios.

Sample size calculation: There is no consensus about what constitutes a clinically
significant difference in treatment between racial and ethnic groups. In the absence of such
a consensus we based our estimates of effect size on previous findings.11, 12 We used
estimates of 75%, 50% and 60% respectively for proportion of whites, African-American, and
Hispanics treated with any analgesic, a two-tailed significance level of 0.05, and a power
of 80% to calculate a sample size of at least 70 patients with long-bone fractures in each
of the three groups.

Two individuals independently entered data into the Statistical Package for the Social
Sciences (SPSS) Data Entry(Chicago, IL). Transcription errors were reconciled by referral to
the original hardcopy of the data collection instrument. We used NQuery 6.0 ( Saugus, MA)
for the sample size calculation, and SPSS version 15.0 (Chicago, IL).

Inclusion Criteria:

- 18 to 55 years;

- Acute pain starting no more than 24 hours before presenting to the ED;

- Have isolated long-bone fracture documented on x-ray;

- Have a complaint of pain at triage or complaining of pain to the physician;

- English and Spanish speaking

Exclusion Criteria:

- Participating in another clinical study at the same site time of entry;

- Unable to complete the pain intensity scale, or complete the questionnaire because of
inability to understand the task and questions;

- Intoxication with alcohol or other drug;

- Pregnancy;

- Methadone use;

- Use of opioids or tramadol in past seven days;

- Patients who are allergic to any analgesics;

- Patients with a chronic pain syndrome (sickle cell anemia, fibromyalgia, migraine,
peripheral neuropathies)