Irene Vikman

Sensitivity and specificity of fall detection in people aged 40 years and over

About one third of home-dwelling people over 65 years of age fall each year. Falling, and the fear of falling, is one of the major health risks that affects the quality of life among older people, threatening their independent living. In our pilot study, we found that fall detection with a waist-worn triaxial accelerometer is reliable with quite simple detection algorithms. The aim of this study was to validate the data collection of a new fall detector prototype and to define the sensitivity and specificity of different fall detection algorithms with simulated falls from 20 middle-aged (40-65 years old) test subjects. Activities of daily living (ADL) performed by the middle-aged subjects, and also by 21 older people (aged 58-98 years) from a residential care unit, were used as a reference. The results showed that the hardware platform and algorithms used can discriminate various types of falls from ADL with a sensitivity of 97.5% and a specificity of 100%. This suggests that the present concept provides an effective method for automatic fall detection.

Comparison of real-life accidental falls in older people with experimental falls in middle-aged test subjects

Falling is a common accident among older people. Automatic fall detectors are one method of improving security. However, in most cases, fall detectors are designed and tested with data from experimental falls in younger people. This study is one of the first to provide fall-related acceleration data obtained from real-life falls. Wireless sensors were used to collect acceleration data during a six-month test period in older people. Data from five events representing forward falls, a sideways fall, a backwards fall, and a fall out of bed were collected and compared with experimental falls performed by middle-aged test subjects. The signals from real-life falls had similar features to those from intentional falls. Real-life forward, sideways and backward falls all showed a pre impact phase and an impact phase that were in keeping with the model that was based on experimental falls. In addition, the fall out of bed had a similar acceleration profile as the experimental falls of the same type. However, there were differences in the parameters that were used for the detection of the fall phases. The beginning of the fall was detected in all of the real-life falls starting from a standing posture, whereas the high pre impact velocity was not. In some real-life falls, multiple impacts suggested protective actions. In conclusion, this study demonstrated similarities between real-life falls of older people and experimental falls of middle-aged subjects. However, some fall characteristics detected from experimental falls were not detectable in acceleration signals from corresponding heterogeneous real-life falls.

Sensitivity and false alarm rate of a fall sensor in long-term fall detection in the elderly

Background: About a third of home-dwelling older people fall each year, and institutionalized older people even report a two- or threefold higher rate for falling. Automatic fall detection systems have been developed to support the independent and secure living of the elderly. Even though good fall detection sensitivity and specificity in laboratory settings have been reported, knowledge about the sensitivity and specificity of these systems in real-life conditions is still lacking. Objective: The aim of this study was to evaluate the long-term fall detection sensitivity and false alarm rate of a fall detection prototype in real-life use. Methods: A total of 15,500 h of real-life data from 16 older people, including both fallers and nonfallers, were monitored using an accelerometry-based sensor system with an implemented fall detection algorithm. Results: The fall detection system detected 12 out of 15 real-life falls, having a sensitivity of 80.0%, with a false alarm rate of 0.049 alarms per usage hour with the implemented real-time system. With minor modification of data analysis the false alarm rate was reduced to 0.025 false alarms per hour, equating to 1 false fall alarm per 40 usage hours. Conclusion: These data suggest that automatic accelerometric fall detection systems might offer a tool for improving safety among older people.

Incidence and seasonality of falls amongst old people receiving home help services in a municipality in northern Sweden

Objectives. Falls among old people is a well-documented phenomenon; however, falls among people living in the community and receiving home help services have been under-researched. The aim of this study was to investigate the incidence, including possible seasonal variation, circumstances and injuries related to falls among community living home help receivers, and to investigate whether fall incidence is associated with the type and amount of home help services received. Study design. Prospective cohort study. Methods. All 614 persons aged 65 and over who were living in a particular northern Swedish community and receiving municipality home help were included. Data on age, sex and home help service use were collected from home help service records, and falls were reported by staff on report forms specifically designed for the study. Results. A total number of 264 falls were recorded among 122 participants. The overall fall incidence was 626 per 1,000 PY, and incidence rate ratios were significantly correlated to the total amount of services used (p&0.001), as well as to the degree of help for I-ADL needs (p&0.001), P-ADL needs (p&0.001) and escort service (p=0.007). The proportion of falls reported as resulting in injury was 33%. The monthly fall incidence was significantly associated to daylight photoperiod, however it was not associated to temperature. Conclusions. Fall incidence among home help receivers aged 65 and over seems correlated to the amount of services they receive. This is probably explained by the fact that impairments connected to ADL limitations and home help needs also are connected to an increased risk of falls. This implies that fall prevention should be considered when planning home help care for old people with ADL limitations. Further research on the connection between daylight photoperiod and fall incidence in populations at different latitudes is needed.

Self-care for minor illness

AIM To describe experiences with and knowledge of minor illness, self-care interventions used in minor illness and channels of information used when providing self-care for minor illness. BACKGROUND Although minor illness is self-limiting, symptoms can be substantial and have a great impact on the affected persons wellbeing. Possibilities to seek and find information about health and self-care have significantly increased through internet-based communities, forums, and websites. Still, a considerable number of consultations with general practitioners are for conditions that are potentially self-treatable. Seeking advanced care for minor illnesses is costly for society and can create discomfort for patients as they are down-prioritized at emergency departments. METHODS Study participants were recruited randomly from the Swedish Address Register. A questionnaire was sent out, and the final sample included 317 randomly selected persons aged 18-80 and living in Sweden. FINDINGS Having experienced a specific illness correlated with self-reported knowledge. Preferred self-care interventions differed between different conditions, but resting and self-medicating were commonly used, along with consulting health care facilities. Compliance to advice was the highest for official information channels, and family members were a popular source of advice.

Sore throat in women after intubation with 6.5 or 7.0 mm endotracheal tube: A quantitative study

BACKGROUND Women experience more sore throats than men after endotracheal intubation. AIM The aim of this study was to investigate the incidence of self-rated sore throat immediately, and 2-4 hours postoperatively, in women after elective gynaecological surgery under general anaesthesia using an endotracheal tube (ETT) size 6.5 or 7.0mm in inner diameter. METHOD Eighty-two female participants who had undergone elective gynaecological surgery participated, 44 and 38 were intubated with size 6.5 mm ETT and 7.0mm ETT respectively. They estimated the occurrence of sore throat preoperatively and postoperatively, according to a 4-point Likert scale. Statistical data were analysed using the Package for Social Science (SPSS) 19. RESULTS Sore throat was present in 29.5% of participants who were intubated with size 6.5 mm ETT immediately postoperatively and in 39.5% of those who were intubated with size 7.0 mm ETT. CONCLUSION Nurses specialising in the supervision of daily care specific to the intubated patient should note and alleviate sore throat as part of their nursing care.

The second myocardial infarction: Higher risk factor burden and earlier second myocardial infarction in women compared with men. The Northern Sweden MONICA study:

Background: Several studies have examined various parameters and experiences when patients suffer their first myocardial infarction (MI), but knowledge about when they suffer their second MI is limited. Aim: To compare risk factors for MI, that is, diabetes, hypertension and smoking, for the first and second MI events in men and women affected by two MIs and to analyse the time intervals between the first and second MIs. Methods: A retrospective cohort study of 1017 patients aged 25–74 years with first and second MIs from 1990 through 2009 registered in the Northern Sweden MONICA registry. Results: More women than men have diabetes and hypertension and are smokers at the first MI. Similar differences between the genders remain at the time of the second MI for diabetes and hypertension, although both risk factors have increased. Smoking decreased at the second MI without any remaining difference between genders. Women suffer their second MI within a shorter time interval than men do. Within 16 months of their first MI, 50% of women had a second MI. The corresponding time interval for men was 33 months. Conclusion: Patients affected by an MI should be made aware of their risk of recurrent MI and that the risk of recurrence is highest during the first few years after an MI. In patients affected by two MIs, women have a higher risk factor burden and suffer their second MI earlier than men do and thus may need more aggressive and more prompt secondary prevention.

Psychometric evaluation of a Swedish self-efficacy scale and recovery locus of control scale in the context of minor illness

Reliable and valid instruments are essential when examining the role of self-efficacy and locus of control in the self-care context. The aim of this study was to test the validity and reliability of the Self-Efficacy Scale in Self-Care (SESSC) and the Swedish version of the Recovery Locus of Control scale (RLoC) in the context of minor illness. A descriptive correlational design was used to assess the psychometric characteristics of the scales. The study population was 317 randomly selected Swedish inhabitants aged 18-80. The results from this study showed that the RLoC has limitations in reliability and validity and should not be applied in the context of self-care of minor illness. The SESSC proved to be a reliable and valid instrument in assessing self-efficacy in self-care for minor illness.

Patients' Perceptions of Perioperative Quality of Care in Relation to Self-rated Health

Purpose: To explore (1) associations between patient and perioperative factors and dimensions of quality of care and (2) perioperative patients’ self‐rated physical health in relation to information, encouragement, and participation. Design: A nonexperimental descriptive exploratory design (n = 170 participants). Methods: Analyses were performed using quantitative techniques; collected data were quantitative in nature. Multiple logistic regression and Mann‐Whitney U tests were used to analyze the data. Findings: The factor associated with patients’ satisfaction within the dimension of “identity‐oriented approach of the caregivers,” including the quality of information, encouragement, and participation, was self‐estimated physical health. Those who estimated their physical health as being good were generally more satisfied. Patients who rated their physical health as being less than good were significantly less satisfied with the information provided before surgery about their stay in the postanesthesia care unit (PACU). Conclusions: Nurses should chart patients’ estimations of their physical health initially in care to provide reinforced support for patients who estimate their physical health is less than good. Before surgery, patients who have estimated their physical health as being less than good should be given realistic information about their stay in the PACU—that they will be in a PACU after surgery, what that stay means, and why it is necessary.

Decline in sensorimotor systems explains reduced falls self-efficacy

Physical performance including balance tasks is one of the main factors explaining the variance in falls self-efficacy in older adults. Balance performance is often measured by use of gross assessment scales, which assess the result of integration of all systems involved in postural control. We aimed to investigate which measurements of postural control correlate to falls self-efficacy scores as measured by the FES-I instrument, and which sensory and motor systems best explain them. A cross sectional study was designed, in which 45 older adults performed quiet stance and limits of stability trials during which their center of pressure (CoP) excursion was recorded. Falls self-efficacy was measured using the Falls Efficacy Scale - International. Eyesight, vestibular function, proprioception, reaction time and strength were also measured. Hierarchical orthogonal projection of latent structures was used to model FES-I with the CoP trials and then with the sensory and muscle function data. Fes-I could be explained to 39%, with the eyes open trials and the limits of stability trials loading the heaviest. The base model could be explained to 40% using the sensory and muscle function data, with lower limb strength, leg proprioception, neck proprioception, reaction time and eyesight loading the heaviest.