Behavior states are real and observable.

Mudford, Hogg, and Roberts (1999) published additional concerns about their failure to achieve interobserver agreement on adults with mental retardation when using an experimental, 13-category behavior state code we earlier provided to them at their request. They presented findings of interobserver agreements from a videotape of their 3 adult participants that was scored by observers at the University of Kansas. In this response we present extensive investigations demonstrating the reliable measurement of behavior state among infants and adults with mental retardation, including independent data from other state researchers. We give arguments showing why their "videotape study" does not meet requirements for acceptable research methodology and discuss other procedural issues for measuring state behavior among infants with and those without disabilities.

Response to Mudford, Hogg, and Roberts on continuous recording of behavior state.

A recently published article by Modford, Hogg, and Roberts (1997) raised concerns about the observation code used by Guess, Rues, and Roberts (1993) in a longitudinal research project to assess emerging behavior state patterns in infants and young children. Specifically, Mudford et al. found low within-state reliability scores when they used the code with 3 adults who had profound mental retardation. From these findings, Mudford et al. questioned whether the state code satisfies the natural science approach for measuring observable behavior and whether behavior state in only a hypothetical construct. In response, we have raised concerns about the thoroughness of the reliability data collected by Mudford et al. and the conclusions and interpretations they derived from these data.

Replication and extended analysis of behavior state, environmental events, and related variables among individuals with profound disabilities.

Knowledge from previous studies pertaining to state behavior of individuals with profound and multiple disabilities and its relation to other environmental and physiological variables was replicated and extended. Behavior state and environmental data were collected over a 5-hour period for most of 66 students with profound disabilities from 21 educational settings. Results showed general consistency in state patterns and profile groupings with previous investigations, a strong relation between different state profiles and measures of development, and consistency of state patterns across CA levels. Transitional probabilities and z scores were used to confirm changes in state behavior of half of the subjects following primarily adult interactions. Results were discussed in relation to theoretical implications and intervention recommendations.

Some educational implications for students with profound disabilities at risk for inadequate nutrition and the nontherapeutic effects of medication.

The educational relevance for students with profound disabilities of being at risk for poor nutrition and the potential problems caused by the nontherapeutic effects of some medications were examined, examples of their significance presented, some reasons for their occurrence discussed, and some suggestions for instructional personnel offered. Two classroom-based cases were included that described the resolution of a nutritional and a medication problem, including the role of the teacher and health-related personnel.

Analysis of behavior state conditions and associated environmental variables among students with profound handicaps.

State conditions in combination with environmental events and factors significantly affect the level of alertness and responsiveness among students with profound and multiple handicaps. State conditions and environmental variables over a continuous, 5-hour period for each of 25 students in classroom settings were measured. Data were assessed using transitional probability, time series, and correspondence analysis procedures. Results showed the presence of state sequence patterns, short state change periods, and a relatively small amount of association between specific behavior states and the environmental factors and events measured in the study.

Head-erect behavior among three preschool-aged children with cerebral palsy.

This article presents the results of a multiple baseline design, across subjects, to assess the effect of vibratory stimulation on head-erect behavior in subjects who were prone. The subjects were three children with severe multiple handicaps whose mean age was 2 years 4 months and whose conditions included seizures and muscle tone disorders. Frequency of head lifts and cumulative duration of head-erect behavior were recorded during three-minute sessions with the subjects positioned prone on their forearms over a wedge. After baseline observations were recorded, vibration was applied to the paraspinal muscles of the neck and upper back for the first two minutes of each intervention session. In addition, electromyographic activity was recorded for a three-minute session at least once during both the baseline and intervention conditions. Results of the study demonstrated an increase in the cumulative duration of head-erect behavior for the three subjects and an accompanying increase in EMG activity during muscle vibration. The diversity of handicapping conditions (ie, seizures, hypertonia, and hypotonia) appeared to have no effect on the benefits received from muscle vibration for these subjects. Limitations of the study and implications for future research are discussed.