Psychometric validation of the AOSL scale using confirmatory factor analysis: A nationally representative sample.

BACKGROUND: The opioid overdose epidemic has worsened during the COVID-19 pandemic. Recent data revealed a 28.5% increase in drug-related overdose deaths from 2019 to 2020. Adolescents often misuse family members' and friends' prescription opioid medications. Furthermore, adolescents may not possess the knowledge or understanding to safely manage opioid medications. There is a need for a validated scale to effectively measure adolescents' opioid misuse knowledge, attitudes, and interest in learning about prescription opioid safety. OBJECTIVE: The purpose of this study was to validate the Adolescent Opioid Safety and Learning (AOSL) scale with a nationally representative sample of adolescents and confirm the factor structure of the scale using confirmatory factor analysis (CFA). METHODS: Adolescent participants (aged 13-18 years) completed the 16-item AOSL scale in Qualtrics from November to December 2020. A total of 774 responses were analyzed. A CFA was performed to determine the fit of the data to the 4-factor model proposed by a prior exploratory factor analysis of the AOSL scale. Fit was assessed using the chi-square test, comparative fit index (CFI), Tucker-Lewis index (TLI), and root mean-squared error of approximation (RMSEA). RESULTS: Participants were 50% male and 62% white non-Hispanic. The CFI was 0.984, TLI was 0.980, and RMSEA was 0.048 ([95% CI 0.041-0.054], P-value that RMSEA ≤ 0.05 = 0.712). The chi-square test results were χ2 = 268.752 on 98 degrees of freedom (P < 0.001). Cronbach's alpha, a measure of internal consistency, was high within each factor. CFA indicated good fit of the current study's data to the 4-factor model. CONCLUSION: We found the AOSL scale measures adolescents' knowledge of opioid misuse, knowledge of opioid harm, interest in learning about prescription opioids, and likelihood to practice misuse behaviors. This scale can help researchers understand adolescent perceptions and opinions about opioid safety.

Optimizing Flow Cytometric Analysis of Immune Cells in Samples Requiring Cryopreservation from Tumor-Bearing Mice.

Most shared resource flow cytometry facilities do not permit analysis of radioactive samples. We are investigating low-dose molecular targeted radionuclide therapy (MTRT) as an immunomodulator in combination with in situ tumor vaccines and need to analyze radioactive samples from MTRT-treated mice using flow cytometry. Further, the sudden shutdown of core facilities in response to the COVID-19 pandemic has created an unprecedented work stoppage. In these and other research settings, a robust and reliable means of cryopreservation of immune samples is required. We evaluated different fixation and cryopreservation protocols of disaggregated tumor cells with the aim of identifying a protocol for subsequent flow cytometry of the thawed sample, which most accurately reflects the flow cytometric analysis of the tumor immune microenvironment of a freshly disaggregated and analyzed sample. Cohorts of C57BL/6 mice bearing B78 melanoma tumors were evaluated using dual lymphoid and myeloid immunophenotyping panels involving fixation and cryopreservation at three distinct points during the workflow. Results demonstrate that freezing samples after all staining and fixation are completed most accurately matches the results from noncryopreserved equivalent samples. We observed that cryopreservation of living, unfixed cells introduces a nonuniform alteration to PD1 expression. We confirm the utility of our cryopreservation protocol by comparing tumors treated with in situ tumor vaccines, analyzing both fresh and cryopreserved tumor samples with similar results. Last, we use this cryopreservation protocol with radioactive specimens to demonstrate potentially beneficial effector cell changes to the tumor immune microenvironment following administration of a novel MTRT in a dose- and time-dependent manner.