A prospective study evaluating the adhesive tape impression for the diagnosis of dermatophytosis in dogs and cats.

BACKGROUND: Potential contagion and zoonotic risk make rapid diagnosis of dermatophytosis important amongst companion animals. HYPOTHESIS/OBJECTIVES: To compare the adhesive tape impression (ATI), trichogram, Wood's lamp (WL) examination and fungal culture for diagnosis of dermatophytosis, and the ATI and trichogram for ease of use. ANIMALS: Five dogs and 15 cats with consistent lesions, history and at least two positive dermatophyte test results. MATERIALS AND METHODS: After WL examination, one representative lesion per patient was sampled for ATI, trichogram and fungal culture. Microscopic detection of fungal elements on ATI and trichogram were objectively and subjectively compared. The ability of all tests to correctly detect dermatophytosis, and the ability of ATI and trichogram to detect fungal elements in >20 high-powered fields (HPF) were compared using Fisher's exact tests. RESULTS: ATI, trichogram, fungal culture and WL were positive in 100% (20 of 20), 90% (18 of 20), 95% (19 of 20) and 65% (13 of 20) of patients, respectively, with a significant difference between WL and ATI (p = 0.0499). Fungal culture revealed Microsporum. canis (n = 16), Nannizzia gypsea (n = 1), Trichophyton mentagrophytes (n = 1) and T. rubrum (n = 1). Fungal elements were detected in >20 HPF more frequently with ATI (18 of 20) than trichogram (11 of 20) (p = 0.017), and detection required careful scanning to distinguish from background debris more often with trichogram. Fungal elements were located with neutrophil clusters and keratinocyte rafts in addition to abnormal hair fragments more frequently on ATI. CONCLUSIONS AND CLINICAL RELEVANCE: ATI had the highest ability to correctly diagnose dermatophytosis, and increased ease of detecting fungal elements compared to trichogram.

Preliminary analysis on the characteristics of stamps by 3D printing and their stamped impression.

The development of 3D printing technology has brought new risks and challenges to stamp impression identification. To prevent potential risks, a total of 45 stamps were printed using three types of 3D printers: fused deposition molding (FDM) printer, stereo lithography (SLA) printer, and liquid crystal display (LCD)-based SLA 3D printer, including 6 stamps replicated using LCD-based SLA 3D printer. A preliminary study was conducted on the printed stamps and stamped impressions, and the results showed that stamp are influenced by various factors such as printer type, printing material, the technology level of the producer, mold parameters such as font, size, printing parameters, slicing direction, and polishing process, etc., resulting in significant differences in characteristics. However, there are some obviously common characteristics such as missing of strokes, exposure of white and mottled phenomenon in the impression stamped by the 3D produced stamp. The impression of stamp replicated with an LCD 3D printer can be easily identified since it is difficult to achieve consistency with the real impression in detail characteristics.

Influence of scanning pattern on scanning accuracy, scanning time, and number of photograms of complete-arch intraoral implant scans: A clinical study.

OBJECTIVES: To measure the influence of scanning pattern on the accuracy, scanning time, and number of photograms of complete-arch intraoral implant scans. METHODS: A maxillary edentulous patient with 7 implants was selected. The reference implant cast was obtained using conventional methods (7Series Scanner). Four groups were created based on the scanning pattern used to acquire the complete-arch implant scans by using an intraoral scanner (IOS) (Trios4): manufacturer's recommended (Occlusal-Buccal-Lingual (OBL)), zig-zag (Zig-zag), circumferential (Circumf), and novel pattern that included locking an initial occlusal scan (O-Lock group) (n=15). Scanning time and number of photograms were recorded. The linear and angular measurements were used to assess scanning accuracy. One-way ANOVA and Tukey tests were used to analyze trueness, scanning time, and number of photograms. The Levene test was selected to assess precision (α=.05). RESULTS: Statistically significant differences in trueness were detected among OBL, Zig-zag, Circumf, and O-Lock regarding linear discrepancy (P<0.01), angular discrepancy (P<0.01), scanning time (P<0.01), and number of photograms (P<0.01). The O-Lock (63 ±20 µm) showed the best linear trueness with statistically significant differences (P<0.01) with Circumferential (86 ±16 µm) and OBL (87 ±19 µm) groups. The O-Lock (93.5 ±13.4 seconds, 1080 ±104 photograms) and Circumf groups (102.9 ±15.1 seconds, 1112 ±179 photograms) obtained lower scanning times (P<0.01) and number of photograms (P<0.01) than OBL (130.3 ±19.4 seconds, 1293 ±161 photograms) and Zig-zag (125.7 ±22.1 seconds, 1316 ±160 photograms) groups. CONCLUSIONS: The scanning patterns tested influenced scanning accuracy, scanning time, and number of photograms of the complete-arch scans obtained by using the IOS tested. The zig-zag and O-Lock scanning patterns are recommended to obtain complete-arch implant scans when using the selected IOS.

A linkage study investigating sexualized self-presentation on mobile dating apps and user traits.

Mobile Dating Applications (MDAs) are integral to young adults' lives, serving as a platform for romantic and sexual self-presentation during the search for potential partners. Despite its potential link to adverse outcomes including body shame, the prevalence of sexualized self-presentation remains understudied. This pre-registered linkage study addresses this gap by documenting sexualized self-presentation while considering individual differences related to gender, sexual orientation, and body image. Young adults donated MDA (Tinder, Bumble) profile screenshots (nbiographies = 443, npictures = 1277; Mage = 23.15, SD = 2.94; 72.20 % women). Of those 443 participants, 237 additionally completed a body image linkage survey (Mage = 23.36, SD = 2.90; 71.30 % women). Sexualized self-presentation appeared in 4.30 % of biographies and 56.80 % of profile pictures, mainly through sexualized facial expressions. Women, non-heterosexual users, and those holding a more negative body image engaged more in sexualized self-presentation. Platform type and positive body image indicators did not relate to engagement in sexualized self-presentation. Future research is recommended to explore whether the extensive presence of sexualized self-presentations on MDAs impacts users' personal and relational well-being.

Perfect digital impression of natural abutment teeth without using retraction cords.

Digital technologies are gradually gaining ground in dentistry. In particular, taking impressions with intraoral scanners is becoming routine; however, even this must often be preceded by the use of retraction cords. This article presents an innovative technique to record digital impressions of natural tooth abutments using interim restorations relined with impression material instead of retraction cords. In the laboratory, using computer-aided design, the technician can segment the internal surface of the interim restoration and use it to replace the abutment of the intraoral scan, thus obtaining an accurate coping that yields more detailed information about the supragingival and intrasulcular surface of the preparation.

A method of impressing flabby ridge.

Flabby ridge remained a challenge in dental clinical practice to obtain an accurate impression for edentulous patients. During the traditional impression making process, the excessive and displaceable soft tissue are usually compressed. In this article, we presented an impression method by using a modified special stock tray, impression compound and polyvinyl siloxane impression materials.•the suitable stock tray was modified with holes about 5 mm diameter in the corresponding area to the crest of the flabby ridge.•the primary impression was made by position the modified tray with the softened compound impression on the edentulous ridge, avoiding the area of the flabby ridge.•the final accurate impression was obtained by using the light body polyvinyl siloxane impression material.

Complete-arch accuracy of seven intraoral scanners measured by the virtual-fit method.

OBJECTIVES: This study compared the accuracy of seven intraoral scanners (IOS) by the virtual-fit method. METHODS: Four maxillary arches with tooth abutments were scanned with an industrial reference scanner (n=1) and by Aoralscan3, EmeraldS, Helios600, Lumina, Mediti700, Primescan, and Trios5 IOSs (each n=12). Two complete-arch fixed frameworks were designed on each IOS scan with a 70 µm (group 70) and a 90 µm internal cement space (group 70+20, additional 20 µm at the margin). The virtual-fit method was comprised of superimposing the framework designs onto the reference scan using a non-penetrating algorithm simulating the clinical try-in. Internal and marginal gaps were measured. Precision was estimated by the mean absolute errors (MAE). RESULTS: In group 70, Mediti700 (43 µm), Primescan (42 µm), and EmeraldS were in the best homogenous subset for the marginal gap, followed by the Lumina (67 µm), Aoralscan3 (70 µm), and Trios5 (70 µm), whereas Helios600 (118 µm) was in the third subset. Based on the MAE at the margin, Mediti700, Trios5, and EmeraldS were in the first-best homogenous subset, followed by Primescan. Lumina and Helios600 were in the third subset, and Aoralscan3 was in the fourth subset. In group 70+20, the marginal gap was significantly decreased for Lumina and Aoralscan3, whereas MAE significantly decreased for EmeraldS and Aoralscan3. The rank of IOSs was similar for the internal gap. CONCLUSION: EmeraldS, Mediti700, Primescan, and Trios5 meet the marginal and internal fit criteria for fixed tooth-borne complete arch restorations. Increasing the cement space during design could enhance restoration fit. CLINICAL SIGNIFICANCE: The virtual-fit alignment method can effectively evaluate the accuracy of different intraoral scanners, offering valuable clinical guidance for distinguishing among them. Recent software and hardware versions of long-standing IOS manufacturers are suitable for fabricating complete arch restoration.

Addressing Flabby Ridges in Complete Denture Patients: A Case Report.

A common clinical condition affecting the alveolar ridges of the mandibular or maxillary arches is known as a "flabby ridge." This condition involves a superficial region of movable soft tissue. It is particularly prevalent among long-term denture users, especially in the lower anterior region. Flabby ridges occur when hyperplastic soft tissue replaces the alveolar bone, resulting in mobile, hypermobile, and frequently edematous tissue. This condition is most commonly found in the edentulous areas of the oral cavity, especially in the maxillary anterior region. To provide a good fit for the patient, it is necessary to create a denture with accurate morphology, unique contours, and mobility of flabby tissue. The presence of a flabby ridge can significantly impact the stability, fit, and functionality of dentures. Management of flabby tissue includes various methods such as impression techniques, surgical intervention, and denture designing. This case report aims to provide an improved and controlled application of polyvinyl siloxane impression material in managing flabby tissue conditions, which is commonly used in dental practices. It presents a modified window technique for making impressions of anterior mandibular flabby tissues with their natural, undistorted state, leading to a more accurate and stable denture fit.

Camouflaging, internalized stigma, and mental health in the general population.

BACKGROUND: Camouflaging, the strategies that some autistic people use to hide their differences, has been hypothesized to trigger mental health ramifications. Camouflaging might reflect ubiquitous impression management experiences that are not unique to autistic people and similarly impact the mental health of non-autistic people. AIMS: We first examined whether individuals in the general population camouflage and manage impressions while experiencing mental health repercussions, and how gender and neurodivergent traits modified these associations. We then assessed how camouflaging and impression management arose from internalized stigma, and their inter-relationships in shaping mental health outcomes. METHODS: Data were collected from 972 adults from a representative U.S. general population sample, with measures pertaining to camouflaging, impression management, mental health, internalized stigma, and neurodivergent traits. Multivariate hierarchical regression and moderated mediation analyses were used to address the two research aims. RESULTS: Both camouflaging and self-presentation (a key component of impression management) were associated with mental health presentations in the general population, which overlapped with those previously reported in autistic people. These associations were more pronounced in women compared with men and were of different directions for individuals with higher autistic traits versus higher ADHD traits. Internalized stigma might be a key stressor that could elicit camouflaging and impression management through social anxiety, which in turn might lead to adverse mental health outcomes. CONCLUSIONS: These findings advance the conceptual clarity and clinical relevance of camouflaging and impression management across social and neurodiverse groups in the general population. The ramifications of camouflaging and impression management underscore the need to alleviate internalized stigma for better mental health across human groups.

Self-control and self-expression.

Does self-control express or suppress our true selves? This article reviews the emerging body of literature on the effect of self-control on authentic self-expression from the actors' (self-signaling) and the observers' (other-signaling) perspective. While actors can experience self-control as either expression or suppression of the self, individual differences in decision-making or personal values can predict when self-control is more likely to be experienced in one way or the other. Self-control also signals to observers both positive (e.g., competent, trustworthy, powerful) and negative (e.g., inauthentic, robotic, less warm) identities, with specific inferences depending on the context (e.g., work vs. fun). Overall, the relationship between self-control and self-expression is more nuanced than earlier research suggested, and several open questions await further investigation.

Helpful or harmful? The effect of a diagnostic label and its later retraction on person impressions.

Diagnostic labels for mental health conditions can inadvertently reinforce harmful stereotypes and exacerbate stigma. If a diagnosis is incorrect and a label is wrongly applied, this may negatively impact person impressions even if the inaccurate label is later corrected. This registered report examined this issue. Participants (N = 560) read a vignette about a hospital patient who was either diagnosed with schizophrenia, diagnosed with major depressive disorder, or not diagnosed with a mental health condition. The diagnostic labels were later retracted strongly, retracted weakly, or not retracted. Participants completed several stigma measures (desire for social distance, perceived dangerousness, and unpredictability), plus several inferential-reasoning measures that tested their reliance on the diagnostic label. As predicted, each mental health diagnosis elicited stigma, and influenced inferential reasoning. This effect was stronger for the schizophrenia diagnosis compared to the major depressive disorder diagnosis. Importantly, the diagnostic label continued to influence person judgments after a clear retraction (strong or weak), highlighting the limitations of corrections in reducing reliance on person-related misinformation and mental health stigma.

Do intraoral scanning technologies affect the trueness of dental arches with crowding, diastema, and edentulous spaces? A clinical perspective.

OBJECTIVES: To evaluate the trueness of dental arches digitised by two intraoral scanning (IOS) technologies from patients presenting crowding, diastema, and bilateral posterior edentulous space with tilted molar. METHODS: Conventional impressions and dental stone models were generated from three patients presenting the aforementioned dental arch conditions. These models were digitised on a desktop scanner, and the resulting mesh was used as reference. Subsequently, the patients were scanned using confocal based (CF; iTero Element 2) and blue laser-multiscan (BLM; Virtuo Vivo) imaging IOS technology, totalling thirty scans. The meshes from the scans were exported in Standard Tessellation Language format and analysed using Geomagic Control X software. Root mean square (RMS) indicated deviation magnitude. Differences in IOS technologies were evaluated with paired t-tests, and dental arch conditions compared using ANOVA and post-hoc Tukey tests (α=0.05). RESULTS: Digital dental arch from blue laser-multiscan technology showed lower trueness compared to confocal based technology for crowding (p = 0.0084) and edentulous spaces (p = 0.0025) conditions. When the types of oral condition were compared, discrepancies were significantly different for both IOS technologies, featuring the arch with diastema showing the lowest trueness, followed by edentulous spaces and crowding. CONCLUSION: Dental arches presenting crowding and edentulous spaces digitised by blue laser-multiscan technology exhibited greater discrepancies compared to confocal based imaging technology. Furthermore, trueness varied among the dental arch conditions. CLINICAL SIGNIFICANCE: The IOS technology and patient's dental arch condition can influence the trueness of dental arch digitisation. Being aware of these effects allows clinicians to take them into account during scanning procedures, digital planning and manufacturing.

Rehabilitation of Flabby Ridges for Denture Fabrication: An Enigma for Dental Professionals.

Edentulism can be treated with a removable or fixed prosthesis to improve aesthetics, comfort, and function. The firmness of the residual ridge is crucial for providing sufficient support for soft tissue. However, a flabby ridge lacks adequate tissue support, which poses challenges for clinicians during impression-making and prosthesis fabrication. Conventional prosthodontic approaches are typically used to manage flabby ridges. This article describes two methods for recording flabby ridges: surgical and unique impression techniques. In the first case, the patient was partially edentulous with a flabby ridge in the lower anterior region. This was removed surgically, and a prosthesis was made conventionally. There has been no relapse in treatment after a follow-up of almost one year. In the second case, the flabby ridge was there in the upper anterior region, which was first excised surgically, but the residual ridge was there; hence, the impression was made by the window technique. After a follow-up of almost nine months, there was a relapse in treatment where a flabby ridge was present in the anterior as well as posterior regions. Hence, again, a window impression was recorded, and a new prosthesis was given to the patient, which yielded satisfactory results. In this article, we have presented two cases of flabby ridges that were successfully treated with surgical and non-surgical techniques followed by special impression techniques. Such analogous cases provide dental professionals with insight into the different lines of treatment, relapse, and further management.

Perceptions of artificial intelligence system's aptitude to judge morality and competence amidst the rise of Chatbots.

This paper examines how humans judge the capabilities of artificial intelligence (AI) to evaluate human attributes, specifically focusing on two key dimensions of human social evaluation: morality and competence. Furthermore, it investigates the impact of exposure to advanced Large Language Models on these perceptions. In three studies (combined N = 200), we tested the hypothesis that people will find it less plausible that AI is capable of judging the morality conveyed by a behavior compared to judging its competence. Participants estimated the plausibility of AI origin for a set of written impressions of positive and negative behaviors related to morality and competence. Studies 1 and 3 supported our hypothesis that people would be more inclined to attribute AI origin to competence-related impressions compared to morality-related ones. In Study 2, we found this effect only for impressions of positive behaviors. Additional exploratory analyses clarified that the differentiation between the AI origin of competence and morality judgments persisted throughout the first half year after the public launch of popular AI chatbot (i.e., ChatGPT) and could not be explained by participants' general attitudes toward AI, or the actual source of the impressions (i.e., AI or human). These findings suggest an enduring belief that AI is less adept at assessing the morality compared to the competence of human behavior, even as AI capabilities continued to advance.

A second chance for first impressions: evidence for altered impression updating in borderline personality disorder.

BACKGROUND: Individuals with borderline personality disorder (BPD) frequently alter between idealizing and devaluing other persons, which has been linked to an increased tendency to update self-relevant beliefs and impressions. We hypothesized that increased impression updating could stem from reduced attitude contextualization, i.e., a process in which impression-disconfirming information is linked to contextual cues. METHODS: Individuals diagnosed with BPD and controls (recruited online, with unknown diagnostic status) completed an impression formation paradigm. They first learned about the positive or negative behaviors of others in one Context A (e.g., Person 1 is helpful), followed by learning about behaviors of the opposite valence in a second Context B (Person 1 is rude). We also manipulated between participants whether the observed behaviors were directed toward the study participants (self-relevant) or, more generally, at other people (other-relevant). The contexts were marked by differently-colored backgrounds (e.g., yellow vs. blue), to avoid influences of prior knowledge or experiences. After exposure to information in both contexts, participants rated their impressions of the persons in Context A, Context B, and, crucially, a previously unknown Context C (white background). We examined whether the initial or an updated impression (re-)emerged in Context C. RESULTS: Initial impressions remained stable and dominated the ratings of controls across contexts A, B, and C for both self-relevant and other-relevant behaviors, consistent with contextualizing impression-disconfirming information. As expected, however, individuals with BPD only showed updated impression ratings in Context C for self-relevant behaviors, consistent with the assumed reduced tendency to contextualize impression-disconfirming self-relevant information. Further exploratory analyses suggest that more severe BPD symptoms predicted more pronounced impression updating in the self-relevant condition. CONCLUSIONS: The findings help to illuminate the mechanisms underlying interpersonal problems in individuals with BPD. People with BPD are not just more inclined to discard positive first impressions but to re-evaluate disliked others when they behave positively, contributing to the volatility of interactions with others. Contextualization has known and modifiable antecedents, and the study may thus provide potential targets for therapeutic intervention. Future studies will need to replicate the findings with specified controls.

Striving for Excellence: Fabrication of Complete Denture in a Patient With Flabby Ridges Using Specialized Impression Technique.

Tissue growth across the ridges is a typical clinical feature in the mandibular and maxillary arches. This excess tissue is known as flabby ridges. The mobile tissue may be distorted throughout the impression-making process due to the forces applied. The chewing forces will displace the denture if it is not adequately maintained, which will eventually cause the denture to lose its stability, support, and retention. The particular impression technique promoted accurately documenting flabby ridges. Several strategies, including implant therapy, balanced occlusal load distribution, surgical management, and special impression techniques, can be used to treat removable dentures with "flabby ridges." This case study demonstrates the method for constructing a complete denture in a patient with flabby ridges using a specialized impression technique. This impression technique helps to record flabby tissue with minimal displacement, improving the stability, support, and retention of complete dentures.

Prosthodontic Rehabilitation of the Flabby Edentulous Maxilla Using Hobkirk's Technique: A Case Report.

Edentulism is characterized by the loss of teeth, which can significantly impact oral health and the quality of life of older patients. Among the challenges faced by individuals with edentulism is the occurrence of flabby ridges, a common consequence of prolonged tooth loss. Flabby ridges, characterized by soft, compressible tissue in the edentulous ridge area, present unique management challenges for dental professionals. Fibrous or flabby alveolar ridges present challenges in the fabrication of predictable prostheses. Impression making, a critical step in prosthodontic treatment, becomes particularly problematic as forces exerted during the process can distort the mobile denture-bearing tissues, which will cause the denture to become unstable and loose. This case report aims at an impression technique that can enhance the treatment outcomes for edentulous patients with fibrous alveolar ridges as this decreases the pressure over flabby tissue.

In vitro evaluation of the impact of intraoral scanner, scanning aids, and the scanned arch on the scan accuracy of edentulous arches.

PURPOSE: To assess the accuracy of complete maxillary and mandibular edentulous arch scans obtained using two different intraoral scanners (IOSs), with and without scanning aids, and to compare these results to those obtained using conventional impression methods. MATERIALS AND METHODS: Two IOSs were used (TRIOS 4 [TRI] and Emerald S [EMR]) to scan maxillary and mandibular typodonts. The typodonts were scanned without scanning aids [TRI_WSA and EMR_WSA groups] (n = 10). The typodonts were then scanned under four scanning aid conditions (n = 10): composite markers [TRI_MRK and EMR_MRK groups], scanning spray [TRI_SPR and EMR_SPR groups], pressure indicating paste [TRI_PIP and EMR_PIP groups], and liquid-type scanning aid [TRI_LQD and EMR_LQD groups]. Conventional impressions of both arches were also made using irreversible hydrocolloids in stock trays [IHC] and using polyvinyl siloxane (PVS) impression material in custom trays (n = 10) which were digitized using a laboratory scanner. Using a metrology software program, all scans were compared to a reference scan in order to assess trueness and to each other to assess precision. Trueness and precision were expressed as the root mean square (RMS) of the absolute deviation values and the statistical analysis was modeled on a logarithmic scale using fixed-effects models to meet model assumptions (α = 0.05). RESULTS: The main effect of arch (p = 0.004), scanner (p < 0.001), scanning aid (p = 0.041), and the interaction between scanner and scanning aid (p = 0.027) had a significant effect on mean RMS values of trueness. The arch (p = 0.015) and scanner (p < 0.001) had a significant effect on the mean RMS values of precision. The maxillary arch had better accuracy compared to the mandible. The TRIOS 4 scanner had better accuracy than both the Emerald S scanner and conventional impressions. The Emerald S had better precision than conventional impressions. The scanning spray and liquid-type scanning aids produced the best trueness with the TRIOS 4 scanner, while the liquid-type scanning aid and composite markers produced the best trueness for the Emerald S scanner. CONCLUSION: The scanned arch and the type of scanner had a significant effect on the accuracy of digital scans of completely edentulous arches. The scanning aid had a significant effect on the trueness of digital scans of completely edentulous arches which varied depending on the scanner used.

Using a three-dimensional-printed device with the patient's maxillary dental impression allows to perform minimally invasive brain biopsies in dogs and cats: a preliminary study.

OBJECTIVE: To develop an innovative process for stereotactic brain biopsies in dogs and cats that would provide a definitive diagnosis and optimize the management of patients with brain lesions. ANIMALS: 4 dogs and 1 cat diagnosed with 1 or more brain lesion(s) underwent brain biopsies between March 24, 2023, and October 25, 2023. METHODS: Based on trajectories selected on images of MRI and CT scan performed on each patient, a computerized software program was used to design a 3-D-printed patient-specific device with maxillary dental impression located on a baseplate to secure the patient's head and with insertion ports for the biopsy instrumentations located on a C-arm. As proof of concept, the device was successfully used in 2 cadavers before being used on clinical patients. All biopsy samples were submitted for histopathological examination. RESULTS: Histological diagnosis was obtained in 80% (4/5) of the cases (choroid plexus tumor, astrocytoma, meningioma, and chronic meningoencephalitis of unknown origin). In 1 patient, the results of biopsy were nondiagnostic; postmortem diagnosis was consistent with a low-grade oligodendroglioma. All the patients were discharged within 24 hours after the procedure without complications. This novel stereotactic system allows the surgeon to perform safe, easy-to-use, inexpensive, and minimally invasive precise brain biopsies in dogs and cats, without complications. CLINICAL RELEVANCE: This unique technique could be applied to any size and type of skull and for any type of brain lesions and would provide diagnostic information that would be valuable for future treatment planning and prognosis.

Care partner-informed meaningful change thresholds for the Clinical Dementia Rating-Sum of Boxes for trials of early Alzheimer's disease.

INTRODUCTION: Consensus definitions of meaningful within-patient change (MWPC) on the Clinical Dementia Rating-Sum of Boxes (CDR-SB) are needed. Existing estimates use clinician-rated anchors in clinically diagnosed Alzheimer's disease (AD) populations. Incorporating the care partner perspective offers important insights, and evaluating biomarker-confirmed cohorts aligns estimates with ongoing trials. METHODS: Anchor-based analyses were conducted to evaluate MWPC on the CDR-SB in early AD (Tauriel; NCT03289143) using Caregiver Global Impression of Change in memory or daily activities. RESULTS: Across time points and anchors, mean CDR-SB changes associated with the "somewhat worse" category ranged from 1.50 to 2.12 in early AD, 1.07 to 2.06 in mild cognitive impairment-AD, and 1.79 to 2.25 in mild AD. DISCUSSION: The proposed ranges are appropriate to define meaningful progression on the CDR-SB in similar cohorts and support the interpretation of treatment benefit through MWPC analyses. Thresholds should be calibrated to the context of use; lower/higher thresholds may be applicable in studies of earlier/later disease over shorter/longer durations. HIGHLIGHTS: Within-patient CDR-SB change thresholds are provided using caregiver-rated anchors. 1.5 to 2.5 points may be an appropriate range in early AD trials of similar durations. Cumulative distribution function plots illustrate the benefit of a given treatment. When selecting thresholds, the target population and study design should be considered.