Guidelines for surveys of the American Pediatric Surgical Association

Pediatric surgery is defined by the rare performance of complex operations in children. As a consequence, pediatric surgeons have difficulty identifying high-level evidence to help guide management decisions. The American Pediatric Surgical Association (APSA) Outcomes and Clinical Trials Committee is dedicated to helping our membership identify best practices and appropriate standards for clinical management of pediatric surgical diseases. Often, the best available evidence will be the opinions and experience of our membership, and therefore, quantifying this experience and opinion correctly is of critical importance. The APSA Outcomes and Clinical Trials Committee has therefore developed guidelines for survey development and administration for use by the APSA membership.

The distribution of perceptual cues in English prevocalic fricatives

Two experiments involving deletion of selected segments of syllables were undertaken to investigate the distribution of perceptual cues and the role of right-to-left coarticulation in fricative vowel monosyllables. From 12 original syllables (/f, theta, s, integral/ in combination with /i, u, a/), manipulations were made so that a group of listeners were exposed to transitionless syllables and isolated segments of syllables. Consonant and vowel recognition scores under these conditions showed that right-to-left coarticulation effects are perceptible, but do not contribute to consonant identification. The vocalic effects shown for many monosyllables were consistent with a normalization hypothesis. In agreement with previous literature, spectral cues in frication determine /s, integral/ recognition. These cues also contribute to the identification of many /f/ and /theta/ syllables.

The conceptual reality of selected distinctive features

An experiment was conducted in which a large group of subjects was asked to categorize speech stimuli. In each subexperiment, two groups of 10 subjects categorized, with immediate feedback, 90 stimuli consisting of six monosyllables arranged in 15 randomized blocks. One group, the feature-contrast group, could solve the categorization task on the basis of a feature contrast or rote memory. The second group, a control group, could operate only on the basis of rote memory. Data are presented for the following features: ± vocalic, ± voice, ± nasal, ± continuant, and ± strident. Results indicate that the nasal, strident, and vocalic features have conceptual reality, that pairing a conceptually real feature with a nonoonceptually real feature does not improve performance, and that the data are not easily related to many existing notions or data concerning distinctive-feature theory.