Tolerability and blinding of high-definition transcranial direct current stimulation among older adults at intensities of up to 4 mA per electrode.

BACKGROUND: Few studies have investigated tolerability, blinding, and double-blinding of High-Definition transcranial Direct Current Stimulation (HD-tDCS) at amplitudes above 2 milliamps (mA). OBJECTIVE: We examined a) tolerability of HD-tDCS during stimulation sessions and b) blinding and double blinding of participants and study team members. METHODS: Data from a mixed neurologic sample of 292 older adults were pooled from 3046 HD-tDCS sessions (2329 active; 717 sham). Per electrode amplitudes ranged from 1 mA to 4 mA with total currents up to 10 mA. Participants completed a standardized sensation (tolerability) questionnaire after each session. Participants and study team members stated whether the participant received active or sham stimulation at the end of various sessions. Data were collapsed into the presence/absence of a symptom due to low rates of positive responding and were analyzed for both differences and bioequivalency. RESULTS: There were no safety-related adverse events. HD-tDCS was well tolerated with mostly no ("none") or "mild" sensations reported across sessions, regardless of active or sham condition and in both stimulation naïve and experienced participants. There were no significant differences in side effects between active and sham, with some achieving bioequivalence. Tingling and itching were significantly more common after lower (<2 mA) than higher (≥3 mA) amplitude active sessions, while skin redness was significantly more common after higher amplitudes. Blinding was effective at the participant and study team levels. CONCLUSIONS: HD-tDCS was well tolerated with center electrode amplitudes up to 4 mA. The bimodal ramp-up/down format of the sham was effective for blinding. These results support higher scalp-based amplitudes that enable greater brain-based current intensities in older adults.

Validation of the Arabic Maternal Breastfeeding Evaluation Scale (MBFES-A) among Lebanese women.

BACKGROUND: Maternal satisfaction with the breastfeeding experience is an important determinant of breastfeeding success. There is currently no valid tool to measure perceived maternal satisfaction with breastfeeding in the Arab context. METHODS: This cohort study tested the Maternal Breastfeeding Evaluation Scale (MBFES) on 450 healthy Lebanese mothers for internal consistency reliability and construct validity. Participants were recruited between April 2018 and February 2020. RESULTS: The Cronbach's alpha reliability coefficient of the Arabic MBFES (MBFES-A) was 0.87. Exploratory factor analysis revealed that it has three components: Infant Satisfaction/Growth, Maternal Enjoyment/Role Attainment, and Lifestyle/Body Image with reliability coefficients of 0.88, 0.87, and 0.68, respectively. Four items were deleted because of low factor loadings and three items were relocated to the Infant Satisfaction/Growth subscale based on their factor loadings. Participants who were exclusively breastfeeding at one and/or 3 months had higher mean MBFES-A total and Infant Satisfaction/Growth and Maternal Enjoyment/Role Attainment subscale scores than participants who were partially breastfeeding, and significantly higher mean scores than mothers who were not breastfeeding (all p values < 0.001), findings that support the scale's construct validity. Moreover, scores on the Infant Satisfaction/Growth subscale correlated with exclusive breastfeeding at one (r = 0.37, p < 0.001) and 3 months (r = 0.31, p < 0.001). The MBFES-A score had positive modest correlations with maternal attitude towards breastfeeding (r = 0.30, p < 0.001), exclusive breastfeeding at one (r = 0.27) and at 3 months (r = 0.26, p < 0.001 for both), as well as with the longest previous exclusive breastfeeding (r = 0.27, p < 0.001). CONCLUSIONS: The 26-item MBFES-A is a reliable and valid instrument to use in future breastfeeding research in Middle East North Africa countries. There is a need for replication of our findings in other Arab contexts using new constructs to establish stronger construct validity.