Physical and psychometric measurements
Anthropometric measurements: Height was measured with 1 cm precision with the participant standing without shoes against the measurement scale fastened to the wall. Weight was measured using a balance scale (Seca, Vogel & Halke, Hamburg). It was calibrated by weights at the beginning of the examination at each research site. The examinee was weighed without shoes in light indoor clothing. The measurer estimated the weight of the clothes, in summer in average 1 kg and in winter 2 kg. These were subtracted from the result of the scale and the result was entered with a 1 kg precision. The body mass index (kg/m2) was calculated. Triceps skinfold was measured from the middle of the back of the brachium as a vertical fold of skin. When the upper limb hung without restraint, subscapular skinfold was measured as a horizontal fold of skin under the lower corner of the shoulder blade (Tanner 1959). Two calibrated weekly alternating instruments (British Indicators Ltd, John Bull, Harpenden Skinfold Caliper) were used.
Blood pressure and the pulse: Systolic and diastolic blood pressure and the pulse were measured from the right brachium after 5 minutes rest, twice with a 1.5 -minutes interval. A mercury manometer (Erkameter Original), with attached long cuffs, was used. The size of the rubber bags of the cuff was 12,5 X 40 cm. The stethoscopes were funnel-shaped. The blood pressure was measured by dropping the pressure of the cuff 2 – 3 mmHg per second. The appearance of the sound was recorded as the systolic blood pressure and the disappearance as diastolic blood pressure. The blood pressure was registered with a precision of 2 mmHg.
Upper and lower limb measurement: For individuals invited to the clinical examination because of claudication symptoms, upper and lower limb measurements using doppler-technique were performed. In addition an age- and sex-matched control sample, which did not satisfy the claudication symptom screening criteria, was investigated (Method folder 3.24).
Spirometry: Maximum respiratory capacity (VC), forced maximal respiratory capacity (FVC) and forced expiratory capacity in one second (FEV1) were measured using standard Vitalograph apparatus (Vitalograph Ltd) printing ATPS-values, which were corrected to BTPS-values. The peak expiratory flow (PEF) was measured using the Wright peak flow meter (Airmed Ltd). An effort was made to obtain 3 successful exhalations and the best result was recorded (MS024, Thurlbeck 1976, Vasankari et al. 2010) (Method folder 3.21).
Resting ECG: The usual 12-leads resting -ECG registration was performed using the instrument Olli 308 (Ollituote Oy; KONE Oy). The registration speed was 50 mm/s. The registration was performed by 4 experienced technicians, who pairwise rotated one week at a time. The definition of the exact position of the electrodes, the processing of the skin, and the fastening of the electrodes were performed carefully. The calibration of the device was checked at annual services and at the end of examination. The precision of the device was in accordance with the recommendations (1 mV). Also the speed of the paper stayed correct.
- The registering device transferred the ECG-signal into a digital form and saved it on a magnetic tape (cassette DC 300 A). The magnetic tape cassettes were sent to the computing center of Kuopio University, where they were analyzed. The interpretation was based on Pipberger’s probabilistic program using the orthogonal (XYZ) leads of the ECG (Ahokas et al. 1977, Cornfield et al. 1973, Pipberger et al. 1975).These Data-ECG interpretations are included in the dataset but the interpretation program and the magnetic tapes are missing.
- The ECG-strips (3-channel Siemens - Elema - inkjet printer) were classified according to the updated Minnesota code (Rose and Blackburn 1968). The observers worked pairwise independently from each other. In case the codes differed, the ECG was re-coded. If an inconsistency in the interpretation still remained, the cardiologist in charge made the decision (Method folder 3.16-3.20).
Thorax-X-ray was taken of everyone except of pregnant women. Large chest X-rays were taken (PA and the lateral picture). Profile picture was taken from the left side after ingestion of barium paste (Microdrast). The pictures were taken in the clinic cars with a device with automatic light exposure. The focal distance was 135 cm and filmingvoltage 120 kV. The device had an undirected 45 x 45 cm Lysholm N30 and Kodak X-Omatic Regular intensifying screens. The film was Kodak RP, the pictures were developed using Kodak automatic M 6 development device and the time for the development was 1.5 minutes. Two radiologists independently classified the pictures, made the basic measurements for estimation of heart volume and recorded findings for heart, lung and thoracic spine (Aromaa et al. 1978 and 1985). Spondylosis and hyperostosis were evaluated and classified by an acquainted internis (Julkunen et al. 1981) (Method folder 3.32).
Hand radiographs were taken in the clinical phase of the health examination about those who proved screening-positive for musculoskeletal disorders and about a random sample of 20%, altogether about 3595 persons. A posteroanterior view was taken from both hands using a Monodor device. The values were 85 kV, 45 mAs, FED 70 cm, focus size 1.4x1.4 mm, and time 3 seconds. A radiologist assessed findings compatible with rheumatoid arthritis and osteoarthritis (Kellgren-Lawrence grade) for every joint and measured the thickness of the second metacarpal bone and its cortex to compute the metacarpal index, an indicator of osteoporosis (Kärkkäinen 1985, Aho et al. 1989, Haara et al. 2003 and 2006).
Joint function examination (MS014, Heliövaara et al. 1993a) was carried out for every participant at the basic phase of the health examination. A laboratory nurse tested the following activities (grades: no limitation, partial limitation, full limitation): walking on even ground, walking on tiptoes, climbing two standard stairs (20 cm), squatting, lateral lifting of arms, extension of elbows, flexion of elbows, volar flexion of wrists, flexion of fingers 2 to 5, and opponens movements of thumbs.
MS014 Joint function examination
Measurements of muscular strengths: Grip strength of both hands was measured for every participant. Neck endurance and extension strength of lower limbs were measured for those aged 30 to 65 years. Static endurance of back extensor muscles (modified Biering-Sörensen) was measured if the age was 65 years or less, and if there was no contraindication like back pain or heart illness (Mälkiä 1983).
Oral health examination: At the basic phase of the health examination, a special dental nurse observed and classified the number of teeth, cariotic and filled teeth one by one, residual roots, the condition of gums, and need for treatment (Vehkalahti et al. 1991). At the clinical phase, a dentist carried out a clinical examination for every 6th participant (Method folder 3.12).
Cognitive functioning was measured for individuals younger than 75 years. It consisted of ability to concentrate, memory and learning ability, and power of reasoning:
- Ability to concentrate task comprised large font letters placed in 32 rows on an A4 size sheet. The participant was asked to strike over 5 specific letters whilst he/she checked the sheet row by row (Lahtela et al. 1979).
- Memory and learning ability was examined using a word memory test, performed as a group test. There were 10 key words: flame, injury, home, see, ball, sometimes, edge, income, curve, horse. The instructions and words were tape-recorded and were presented by a recorder. The examinees listened three times to the series of words and after each they were expected to write down on paper the words they remembered.
- The examination of reasoning was carried out using partial tests ’series’ and ’classifications’ of the G-factor test, second version, with the aim to roughly measure the analytic and synthetic element of reasoning. In the first test the participant’s insight into change in the figures was evaluated and in the second test his/her ability to see differences and similarities and thus to identify common features was evaluated (Cattell 1960).
Reaction time test measures the speed of central nervous system and motoric regulation system and how smoothly they can handle impulses representing the concepts attention, vigilance, vitality and focusing. Rate of reaction was measured as the time between the impulse and the response. The rates of reactions and the number of incorrect reactions were registered. Because of disturbance in the function of the device and problems in the interpretation of the produced strips, the results cannot be used in their current form.
