Measuring local genetic variation in permethrin-resistant head lice (Phthiraptera: Pediculidae) from Buenos Aires, Argentina.

The cosmopolitan ectoparasite human head louse, Pediculus humanus capitis (De Geer)(Phthiraptera:Pediculidae), affects mostly school-aged children, with infestations reported every year mainly due to louse resistance to pyrethroids. One of the main resistance mechanisms of pyrethroids is the target site insensitivity (kdr), which is caused by single-nucleotide point mutations (SNPs) located in the voltage-sensitive sodium channel gene. In this study, we analyzed individual head lice toxicologically via the description of their susceptibility profile to permethrin and genetically through the genotypification of their kdr alleles as well as nuclear microsatellite loci. Lice were collected from 4 schools in the city of Buenos Aires, Argentina. The resistance ratios varied from 33.3% to 71.4%, with a frequency of the T917I kdr mutation of 87.31% and with 83.6% of the head lice being homozygous resistant to pyrethroids. Microsatellite data indicated that all the louse school populations had genotype proportions that deviated from Hardy-Weinberg expectations, with FIS > 0 reflecting a deficit of heterozygotes. Bottleneck analysis suggested that all louse school populations underwent a recent reduction in population sizes, while 3 of the 4 schools had gene flow values around 1, indicating ongoing gene flow among those schools. Our study suggests that school louse populations in the city of Buenos Aires may form a metapopulation, where each school represents a small population that undergoes extinction and recolonization processes under strong permethrin selection. This is the first multilevel analysis integrating toxicological, kdr-genotyping, and microsatellite data in human louse populations.

Phosphonate-based iron complex for a cost-effective and long cycling aqueous iron redox flow battery.

A promising metal-organic complex, iron (Fe)-NTMPA2, consisting of Fe(III) chloride and nitrilotri-(methylphosphonic acid) (NTMPA), is designed for use in aqueous iron redox flow batteries. A full-cell testing, where a concentrated Fe-NTMPA2 anolyte (0.67 M) is paired with a Fe-CN catholyte, demonstrates exceptional cycling stability over 1000 charge/discharge cycles, and noteworthy performances, including 96% capacity utilization, a minimal capacity fade rate of 0.0013% per cycle (1.3% over 1,000 cycles), high Coulombic efficiency and energy efficiency near 100% and 87%, respectively, all achieved under a current density of 20 mA·cm-². Furthermore, density functional theory unveils two potential coordination structures for Fe-NTMPA2 complexes, improving the understanding between the ligand coordination environment and electron transfer kinetics. When paired with a high redox potential Fe-Dcbpy/CN catholyte, 2,2'-bipyridine-4,4'-dicarboxylic (Dcbpy) acid and cyanide (CN) ligands, Fe-NTMPA2 demonstrates a notably elevated cell voltage of 1 V, enabling a practical energy density of up to 9 Wh/L.

Genomic Diversity in the Endosymbiotic Bacteria of Human Head Lice.

Insects have repeatedly forged symbioses with heritable microbes, gaining novel traits. For the microbe, the transition to symbioses can lead to the degeneration of the symbiont's genome through transmission bottlenecks, isolation, and the loss of DNA repair enzymes. However, some insect-microbial symbioses have persisted for millions of years, suggesting that natural selection slows genetic drift and maintains functional consistency between symbiont populations. By sampling in multiple countries, we examine genomic diversity within a symbiont species, a heritable symbiotic bacterium found only in human head lice. We find that human head louse symbionts contain genetic diversity that appears to have arisen contemporaneously with the appearance of anatomically modern humans within Africa and/or during the colonization of Eurasia by humans. We predict that the observed genetic diversity underlies functional differences in extant symbiont lineages, through the inactivation of genes involved in symbiont membrane construction. Furthermore, we find evidence of additional gene losses prior to the appearance of modern humans, also impacting the symbiont membrane. From this, we conclude that symbiont genome degeneration is proceeding, via gene inactivation and subsequent loss, in human head louse symbionts, while genomic diversity is maintained. Collectively, our results provide a look into the genomic diversity within a single symbiont species and highlight the shared evolutionary history of humans, lice, and bacteria.

Protease-Induced Excitation of Dorsal Root Ganglion Neurons in Response to Acute Perturbation of the Gut Microbiota Is Associated With Visceral and Somatic Hypersensitivity.

BACKGROUND & AIMS: Abdominal pain is a major symptom of diseases that are associated with microbial dysbiosis, including irritable bowel syndrome and inflammatory bowel disease. Germ-free mice are more prone to abdominal pain than conventionally housed mice, and reconstitution of the microbiota in germ-free mice reduces abdominal pain sensitivity. However, the mechanisms underlying microbial modulation of pain remain elusive. We hypothesized that disruption of the intestinal microbiota modulates the excitability of peripheral nociceptive neurons. METHODS: In vivo and in vitro assays of visceral sensation were performed on mice treated with the nonabsorbable antibiotic vancomycin (50 µg/mL in drinking water) for 7 days and water-treated control mice. Bacterial dysbiosis was verified by 16s rRNA analysis of stool microbial composition. RESULTS: Treatment of mice with vancomycin led to an increased sensitivity to colonic distension in vivo and in vitro and hyperexcitability of dorsal root ganglion (DRG) neurons in vitro, compared with controls. Interestingly, hyperexcitability of DRG neurons was not restricted to those that innervated the gut, suggesting a widespread effect of gut dysbiosis on peripheral pain circuits. Consistent with this, mice treated with vancomycin were more sensitive than control mice to thermal stimuli applied to hind paws. Incubation of DRG neurons from naive mice in serum from vancomycin-treated mice increased DRG neuron excitability, suggesting that microbial dysbiosis alters circulating mediators that influence nociception. The cysteine protease inhibitor E64 (30 nmol/L) and the protease-activated receptor 2 (PAR-2) antagonist GB-83 (10 µmol/L) each blocked the increase in DRG neuron excitability in response to serum from vancomycin-treated mice, as did the knockout of PAR-2 in NaV1.8-expressing neurons. Stool supernatant, but not colonic supernatant, from mice treated with vancomycin increased DRG neuron excitability via cysteine protease activation of PAR-2. CONCLUSIONS: Together, these data suggest that gut microbial dysbiosis alters pain sensitivity and identify cysteine proteases as a potential mediator of this effect.

Risk Factors Associated with Unsuccessful High-Resolution Manometry.

High-resolution manometry (HRM) is used to evaluate the esophageal motor function. Unfortunately, there are times when testing cannot be performed accurately. Our study aimed to quantify the occurrence of failed HRM and identify the associated risk factors. HRM tests were retrospectively collected between September 2021 and August 2022. HRM reports that could not be interpreted based on standard HRM protocol as per Chicago guidelines were classified as failed tests. Information reviewed included testing indications, patient demographics, previous medical/symptom history, and follow-up testing for failed HRM. We then compared patients with successful vs. unsuccessful HRM based on our pre-specified factors. 152 HRM tests were performed, of which 28 tests (18%) were unsuccessful. Factors associated with failed manometry included a history of nausea/vomiting, dyspepsia, and achalasia. Patients who were unable to tolerate the probe during testing were more likely to have a history of dyspepsia (OR 20.3, p = < 0.001) and/or nausea/vomiting (OR 13.8, p = < 0.001). A history of achalasia was found to have an odds ratio of 13.2 when examining failure because of curling of the manometry catheter (p = 0.012). All seven patients who had repeat HRM with endoscopic placement were successful in obtaining diagnostic information. There are two groups that have risk factors for unsuccessful HRM testing. A history of nausea/vomiting and dyspepsia symptoms were associated with being unable to tolerate the manometry probe. The second group comprises patients with a history of achalasia in whom probe curling is more common. Future research targeting these risk factors may minimize diagnostic and treatment delays.

Police-Identified Psychological Distress, Substance Use, and Physical Violence Among Male Intimate Partner Stalkers.

Risk factors for stalking violence are not well understood and few studies have examined psychological distress and substance use specifically. This study aimed to assess whether factors extant in police data could predict severity of stalking violence against intimate partner victims. Western Australia Police Force provided data for 603 men linked to a stalking charge relating to a female intimate partner. Binomial logistic regressions showed police-identified histories of psychological distress and drug use predicted moderate violence, but not severe violence. A co-occurring history of drug use and alcohol use was the strongest predictor of moderate violence (OR = 6.8). These findings suggest accounting for violence severity and substance type when examining stalking violence risk factors. Whether psychological distress and/or substance use were active problems for the men during their stalking behavior is unknown, however the detection of these problems may indicate an unmet need for treatment among this group.

The mediating role of posttraumatic stress disorder symptoms in pain cognitions among Veterans with chronic pain.

Symptoms of posttraumatic stress disorder (PTSD) are highly prevalent among Veterans with chronic pain. Considerable research has examined the intersection of chronic pain and PTSD symptoms. However, it remains unclear whether changes in PTSD may potentially serve a mechanistic role in improving unhelpful pain cognitions for individuals with chronic pain. The present research contributes to the foundational knowledge by addressing this question. Baseline data from a randomized controlled trial targeting pain-related disability for Veterans (n = 103; mean age 43.66; SD = 10.17) with musculoskeletal pain and depression and/or PTSD symptoms were used. Cross-sectional mediation analyses showed that PTSD symptoms mediated the relationship between pain severity and pain catastrophizing, and between pain severity and pain acceptance. After controlling for depression, the mediation involving pain catastrophizing remained significant, while the mediation for pain acceptance did not. Although limitations exist, results point to several treatment recommendations, including ensuring that depressive affect, PTSD-specific symptoms, and attention to both body and mind are included in treatment. Results also provide preliminary evidence for examining these associations longitudinally to improve our understanding of this population and corresponding treatment recommendations.

Coupled Experimental-Theoretical Characterization of a Carbon Electrode in Vanadium Redox Flow Batteries using X-ray Absorption Spectroscopy.

Vanadium redox flow batteries (VRFBs) have emerged as promising solutions for stationary grid energy storage due to their high efficiency, scalability, safety, near room-temperature operation conditions, and the ability to independently size power and energy capacities. The performance of VRFBs heavily relies on the redox couple reactions of V2+/V3+ and VO2+/VO2+ on carbon electrodes. Therefore, a thorough understanding of the surface functionality of carbon electrodes and their propensity for degradation during electrochemical cycles is crucial for designing VRFBs with extended lifespans. In this study, we present a coupled experimental-theoretical approach based on carbon K edge X-ray absorption spectroscopy (XAS) to characterize carbon electrodes prepared under different conditions and identify relevant functional groups that contribute to unique spectroscopic features. Atomic models were created to represent functional groups, such as hydroxyl, carboxyl, methyl, and aldehyde, bonded to carbon atoms in either sp2 or sp3 environments. The interactions between functionalized carbon and various solvated vanadium complexes were modeled using density functional theory. A library of carbon K-edge XAS spectra was generated for distinct carbon atoms in different functional groups, both before and after interacting with solvated vanadium complexes. We demonstrate how these simulated spectra can be used to deconvolve ex situ experimental spectra measured from carbon electrodes and to track changes in the electrode composition following immersion in different electrolytes or extended cycling within a functional VRFB. By doing so, we identify the active species present on the carbon electrodes, which play a crucial role in determining their electrochemical performance.

Expression and function of transient receptor potential melastatin 3 in the spinal afferent innervation of the mouse colon.

Abdominal pain is a cardinal symptom of inflammatory bowel disease (IBD). Transient receptor potential (TRP) channels contribute to abdominal pain in preclinical models of IBD, and TRP melastatin 3 (TRPM3) has recently been implicated in inflammatory bladder and joint pain in rodents. We hypothesized that TRPM3 is involved in colonic sensation and is sensitized during colitis. We used immunohistochemistry, ratiometric Ca2+ imaging, and colonic afferent nerve recordings in mice to evaluate TRPM3 protein expression in colon-projecting dorsal root ganglion (DRG) neurons, as well as functional activity in DRG neurons and colonic afferent nerves. Colitis was induced using dextran sulfate sodium (DSS) in drinking water. TRPM3 protein expression was observed in 76% of colon-projecting DRG neurons and was often colocalized with calcitonin gene-related peptide. The magnitudes of intracellular Ca2+ transients in DRG neurons in response to the TRPM3 agonists CIM-0216 and pregnenolone sulfate sodium were significantly greater in neurons from mice with colitis compared with controls. In addition, the percentage of DRG neurons from mice with colitis that responded to CIM-0216 was significantly increased. CIM-0216 also increased the firing rate of colonic afferent nerves from control and mice with colitis. The TRPM3 inhibitor isosakuranetin inhibited the mechanosensitive response to distension of wide dynamic range afferent nerve units from mice with colitis but had no effect in control mice. Thus, TRPM3 contributes to colonic sensory transduction and may be a potential target for treating pain in IBD.NEW & NOTEWORTHY This is the first study to characterize TRPM3 protein expression and function in colon-projecting DRG neurons. A TRPM3 agonist excited DRG neurons and colonic afferent nerves from healthy mice. TRPM3 agonist responses in DRG neurons were elevated during colitis. Inhibiting TRPM3 reduced the firing of wide dynamic range afferent nerves from mice with colitis but had no effect in control mice.

Response to Marabotto et al.

Biopsies have important value in assessing for nonerosive reflux disease.

Protonation Stimulates the Layered to Rock Salt Phase Transition of Ni-Rich Sodium Cathodes.

Protonation of oxide cathodes triggers surface transition metal dissolution and accelerates the performance degradation of Li-ion batteries. While strategies are developed to improve cathode material surface stability, little is known about the effects of protonation on bulk phase transitions in these cathode materials or their sodium-ion battery counterparts. Here, using NaNiO2 in electrolytes with different proton-generating levels as model systems, a holistic picture of the effect of incorporated protons is presented. Protonation of lattice oxygens stimulate transition metal migration to the alkaline layer and accelerates layered-rock-salt phase transition, which leads to bulk structure disintegration and anisotropic surface reconstruction layers formation. A cathode that undergoes severe protonation reactions attains a porous architecture corresponding to its multifold performance fade. This work reveals that interactions between electrolyte and cathode that result in protonation can dominate the structural reversibility/stability of bulk cathodes, and the insight sheds light for the development of future batteries.

Comparable Minimally Important Differences and Responsiveness of Brief Pain Inventory and PEG Pain Scales across 6 Trials.

The 3-item pain intensity (P), interference with the enjoyment of life (E), and interference with general activity (G), or PEG, has become one of the most widely used measures of pain severity and interference. The minimally important differences (MID) and responsiveness of the PEG are essential metrics for solidifying its role in research and clinical care. The current study aims to establish the MID and responsiveness of the PEG by synthesizing data from 1,710 participants across 6 controlled trials. MIDs were estimated using absolute score changes among individuals reporting their pain was "a little better" on a retrospective global change anchor as well as distribution-based estimates using standard deviation thresholds and 1 and 2 standard errors of measurement. Responsiveness was assessed using standardized response means, area under the curve, and treatment effect sizes. MID estimates for the PEG ranged from 0.60 to 1.1 when using 0.35 SD, and 0.78 to 1.22 using 1 standard error of measurement. MID estimates using the global anchor had somewhat more variability but most estimates ranged from 1.0 to 1.75. Responsiveness effect sizes were generally large (>.80) for standardized response means and moderate (>.50) for treatment effect. Similarly, the most area under the curve values demonstrated an acceptable level of scale responsiveness (≥.70). Importantly, MID estimates and responsiveness of the PEG and BPI scales were largely comparable when aggregating data across trials. Our synthesis indicates that 1 point is a reasonable MID estimate on these 0- to 10-point pain scales, with 2 points being an upper bound. PERSPECTIVE: This article synthesizes data from 6 clinical trials to establish the minimally important difference (MID) and responsiveness of the 3-item PEG pain scale. The PEG demonstrated good responsiveness, and 1 to 2 points proved to be reasonable estimates for the lower and upper bounds of the MID.

Synergistically Stabilizing Zinc Anodes by Molybdenum Dioxide Coating and Tween 80 Electrolyte Additive for High-Performance Aqueous Zinc-Ion Batteries.

Recently, aqueous zinc-ion batteries (ZIBs) have become increasingly attractive as grid-scale energy storage solutions due to their safety, low cost, and environmental friendliness. However, severe dendrite growth, self-corrosion, hydrogen evolution, and irreversible side reactions occurring at Zn anodes often cause poor cyclability of ZIBs. This work develops a synergistic strategy to stabilize the Zn anode by introducing a molybdenum dioxide coating layer on Zn (MoO2@Zn) and Tween 80 as an electrolyte additive. Due to the redox capability and high electrical conductivity of MoO2, the coating layer can not only homogenize the surface electric field but also accommodate the Zn2+ concentration field in the vicinity of the Zn anode, thereby regulating Zn2+ ion distribution and inhibiting side reactions. MoO2 coating can also significantly enhance surface hydrophilicity to improve the wetting of electrolyte on the Zn electrode. Meanwhile, Tween 80, a surfactant additive, acts as a corrosion inhibitor, preventing Zn corrosion and regulating Zn2+ ion migration. Their combination can synergistically work to reduce the desolvation energy of hydrated Zn ions and stabilize the Zn anodes. Therefore, the symmetric cells of MoO2@Zn∥MoO2@Zn with optimal 1 mM Tween 80 additive in 1 M ZnSO4 achieve exceptional cyclability over 6000 h at 1 mA cm-2 and stability (>700 h) even at a high current density (5 mA cm-2). When coupling with the VO2 cathode, the full cell of MoO2@Zn∥VO2 shows a higher capacity retention (82.4%) compared to Zn∥VO2 (57.3%) after 1000 cycles at 5 A g-1. This study suggests a synergistic strategy of combining surface modification and electrolyte engineering to design high-performance ZIBs.

Examining the Veterans Health Administration whole health model of care within the context of posttraumatic stress disorder.

The Veterans Health Administration's Whole Health system of care focuses on offering veterans holistic health approaches and tailoring health care to individual's goals and preferences. The present study assessed factors associated with Whole Health use and its potential benefits among veterans with posttraumatic stress disorder (PTSD) receiving Veterans Health Administration care. This cohort study used retrospective electronic health records combined with survey data (baseline, 6 months) from 18 Veterans Affairs Whole Health pilot implementation sites and compared patient-reported outcomes between veterans who used Whole Health services versus those who did not, among veterans with (n = 1,326) and without (n = 3,243) PTSD. Patient-reported outcomes assessed were pain (PEG), patient-reported outcomes measurement information system physical and mental health functioning, and a one-item global meaning and purpose assessment. Veterans with PTSD were more likely to have used Whole Health (38% vs. 21%) than those without PTSD. Veterans with PTSD who used Whole Health services experienced small improvements over 6 months in physical (Cohen's d = .12) and mental (Cohen's d = .15) health functioning. Veterans without PTSD who used Whole Health services experienced small improvements in physical health (Cohen's d = .09) but not mental health (Cohen's d = .04). Veterans with PTSD were frequently connected with Whole Health services even though implementation efforts were not explicitly focused on reaching this population. Results suggest Whole Health may play an important role in how veterans with PTSD engage with health care. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Prevalence and Genetic Diversity of a Microsporidian Parasite in the Black Imported Fire Ant and Its Social Parasitic Ant (Formicidae: Myrmicinae: Solenopsis) in Buenos Aires Province, Argentina.

Microsporidia are natural pathogens of arthropods and have been used as biological control against insect pests. In the United States, efforts to control the invasive Red Imported Fire Ant, Solenopsis invicta, and Black Imported Fire Ant, Solenopsis richteri, have included the use of the microsporidium, Kneallhazia solenopsae. However, there is limited information about the genetic differences among the microsporidian variants found in S. invicta and in S. richteri. In this study, we assessed the prevalence and genetic diversity of K. solenopsae in native populations of S. richteri in Argentina (South America). Additionally, we examined the social parasitic ant, Solenopsis daguerrei, which is found in some S. richteri nests, for the presence of this microsporidium. The survey of 219 S. richteri nests revealed K. solenopsae infections in all five sites analyzed, with 28 colonies (12.8%) positive for the microsporidium. Among the 180 S. daguerrei individuals collected, seven ants (3.9%) from three sites tested positive for K. solenopsae. Phylogenetic analyses of the microsporidian variants present in S. richteri and S. daguerrei based on partial small subunit ribosomal gene sequences (SSU rRNA) showed that both ant species shared the same variant, which is different from the ones found in S. invicta. Further studies are needed to determine the pathogenicity of genetically different K. solenopsae variants among Solenopsis species.

NG2/CSPG4 attenuates motility in mandibular fibrochondrocytes under serum starvation conditions.

The migration of mandibular fibrochondrocytes is important for the development of the mandible, the homeostasis of the mandibular cartilage, and for the capacity of the tissue to respond to injury. Mandibular fibrochondrocytes have to overcome formidable obstacles during migration including a dense and heterogeneous three-dimensional matrix. Guiding the direction of cell migration and commitment to a migratory phenotype in this microenvironment necessitates a multivalent response to chemotactic and extracellular matrix-mediated stimuli. One of the key matrix components in the cartilage of the temporomandibular joint is type VI collagen. Neuron/glial antigen 2 (NG2/CSPG4) is a transmembrane proteoglycan that binds with collagen VI and has been implicated in a wide range of cell behaviors including cell migration, motility, adhesion, and proliferation. While NG2/CSPG4 has been shown to be a key regulator of mandibular cartilage homeostasis, its role in the migration of mandibular fibrochondrocytes during normal and cell stress conditions has yet to be resolved. Here, we address this gap in knowledge by characterizing NG2/CSPG4-dependent migration in mandibular fibrochondrocytes using primary mandibular fibrochondrocytes isolated from control and full length NG2/CSPG4 knockout mice, in primary mandibular fibrochondrocytes isolated from NG2|DsRed reporter mice and in an immortalized mandibular fibrochondrocyte cell line with a mutated NG2/CSPG4 ectodomain. All three cells demonstrate similar results, with loss of the full length or truncated NG2/CSPG4 increasing the rate of cell migration in serum starvation/cell stress conditions. These findings clearly implicate NG2/CSPG4 as a key molecule in the regulation of cell migration in mandibular fibrochondrocytes in normal and cell stress conditions, underscoring the role of NG2/CSPG4 as a mechanosensitive signaling hub in the mandibular cartilage.

Nuclear genetic diversity of head lice sheds light on human dispersal around the world.

The human louse, Pediculus humanus, is an obligate blood-sucking ectoparasite that has coevolved with humans for millennia. Given the intimate relationship between this parasite and the human host, the study of human lice has the potential to shed light on aspects of human evolution that are difficult to interpret using other biological evidence. In this study, we analyzed the genetic variation in 274 human lice from 25 geographic sites around the world by using nuclear microsatellite loci and female-inherited mitochondrial DNA sequences. Nuclear genetic diversity analysis revealed the presence of two distinct genetic clusters I and II, which are subdivided into subclusters: Ia-Ib and IIa-IIb, respectively. Among these samples, we observed the presence of the two most common louse mitochondrial haplogroups: A and B that were found in both nuclear Clusters I and II. Evidence of nuclear admixture was uncommon (12%) and was predominate in the New World potentially mirroring the history of colonization in the Americas. These findings were supported by novel DIYABC simulations that were built using both host and parasite data to define parameters and models suggesting that admixture between cI and cII was very recent. This pattern could also be the result of a reproductive barrier between these two nuclear genetic clusters. In addition to providing new evolutionary knowledge about this human parasite, our study could guide the development of new analyses in other host-parasite systems.

Introducing the integrated model of co-occurring chronic pain and posttraumatic stress disorder: Adding meaning-making and existential concepts to current theory.

OBJECTIVE: Making meaning out of the experience of chronic pain and posttraumatic stress disorder (PTSD) is a core process of recovery and symptom management of the comorbidity and a key active ingredient in the treatment for these conditions. Managing the effects of chronic pain and PTSD symptoms often evokes anxieties that could be considered existential (e.g., loss of meaning in life and concerns about one's identity). However, current theoretical models of co-occurring chronic pain and PTSD do not capture core meaning-making processes involved in either condition, resulting in the potential to overlook their centrality. The objective of the current work is to integrate current theoretical models of co-occurring chronic pain and PTSD with theory and science related to meaning-making and existential anxiety. METHOD: A targeted literature review was used to develop a novel model of co-occurring chronic pain and PTSD. RESULTS: The present work introduces the integrated model of co-occurring chronic pain and PTSD, which is a first attempt at integrating current theoretical perspectives of co-occurring chronic pain and PTSD with the literature on meaning-making and closely related existential perspectives. We outline model-specific hypotheses and describe model implications and future directions. CONCLUSIONS: The model provides clinicians and researchers with a more thorough conceptualization of how chronic pain and PTSD interact, which symptoms to target, and which outcomes may be important for individuals who have both chronic pain and PTSD. As a result, the model has the potential to improve pain and PTSD outcomes, and perhaps health outcomes more broadly, within this population. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Minimal important difference metrics and test-retest reliability of the PTSD Checklist for DSM-5 with a primary care sample.

The PTSD Checklist for DSM-5 (PCL-5) is a measure of posttraumatic stress disorder (PTSD) symptom severity that is widely used for clinical and research purposes. Although previous work has examined metrics of minimal important difference (MID) of the PCL-5 in veteran samples, no work has identified PCL-5 MID metrics among adults in primary care in the United States. In this secondary analysis, data were evaluated from primary care patients (N = 971) who screened positive for PTSD and participated in a large clinical trial in federally qualified health centers in three U.S. states. Participants primarily self-identified as women (70.2%) and White (70.3%). We calculated test-retest reliability using clinic registry data and multiple distribution- and anchor-based metrics of MID using baseline and follow-up survey data. Test-retest reliability (Pearson's r, Spearman's ρ, intraclass correlation coefficient) ranged from adequate to excellent (.79-.94), with the shortest time lag demonstrating the highest reliability estimate. The MID for the PCL-5 was estimated using multiple approaches. Distribution-based approaches indicated an MID range of 8.5-12.5, and anchor-based approaches indicated an MID range of 9.8-11.7. Taken together, the MID metrics indicate that PCL-5 change scores of 9-12 likely reflect real change in PTSD symptoms and indicate at least an MID for patients, whereas PCL-5 change scores of 5 or less likely are not reliable. These findings can help inform clinicians using the PCL-5 in similar populations to track patient responses to treatment and help researchers interpret PCL-5 score changes in clinical trials.