Biomedical subjects

J Bouma

Publications and source records attributed to J Bouma.

At least 19 recordsLinked to original sources

PubMed2006

Recall bias did not affect perceived magnitude of change in health-related functional status.

BACKGROUND AND OBJECTIVE: It was hypothesized that within an invasively treated group and within a group that improved in angina pectoris no difference in effect size would occur between prospective and retrospective measures. Furthermore, it was hypothesized that assessment of perceived change at post-test may be invalid because of recall bias and present-state bias. STUDY DESIGN AND SETTING: Effect sizes (as standardized response means) were used as indicators of magnitude of change. Linear structural equation analysis (with LISREL) was used to investigate the relationship between the estimates of recall accuracy and retrospectively assessed change. RESULTS: No significant differences were found between prospective and retrospective measures of change over time in health-related functional status. Recall bias was not associated with retrospective measurement of change within a 12-week interval. An expected present-state effect was found in a structural equation model. CONCLUSION: Prospective and retrospective indices of magnitude of change were similar between groups receiving treatment of known efficacy. Recall bias seems to be an acceptable risk in short-term follow-up studies.

Adult↗

PubMed2006

Assessment of severity of hand eczema: discrepancies between patient- and physician-rated scores.

BACKGROUND: In clinical practice or trials on hand eczema the severity of this disease can be 'measured' in different ways: by means of a physician-rated clinical severity score, a patient-rated clinical severity score or by an indicator of the burden of disease. We assume that the patient-rated severity score corresponds more with the (change in) burden of disease than with the physician-rated severity score. OBJECTIVES: To demonstrate how physicians and patients differ in their assessment of the severity of hand eczema as seen in a physician-rated severity score, patient-rated severity score and a burden of disease questionnaire. METHODS: We used data from an open-label randomized controlled trial which was set up in two university hospital dermatology departments in the Netherlands, specializing in hand eczema. One hundred and fifty-eight patients with moderate to severe chronic hand eczema were included. The main outcome measures were the physician-rated severity score, based on five visible aspects of hand eczema (desquamation, erythema, vesicles, infiltration, fissures), the patient-rated severity score (a self-rating scale), a burden of disease questionnaire (the Dermatology Life Quality Index, DLQI) and the correlations between these parameters, both at inclusion and over time. RESULTS: Only desquamation and infiltration were significantly correlated with patient-rated severity score. Patient-rated severity score correlated with seven of 10 DLQI items, but it did not correlate with the items regarding influence on clothes worn, impairment of sporting activities, and problems associated with treatment of the skin. The majority of patients showed improvement in all parameters after treatment. However, the improvement in patient-rated severity score was not clearly correlated with changes in physician-rated severity score. Except for DLQI item 1 (itch, soreness, pain, stinging), none of the changes in burden of disease was correlated with changes in patient-rated severity score. For each DLQI item, change over time correlated weakly with decreases in several, but not all, components of the physician-rated severity score. CONCLUSIONS: Disease severity can be expressed by different scores; these scores are not clearly correlated, and measure different aspects. Patient satisfaction is not guaranteed when treatment is focused solely on the visible aspects of hand eczema. Instead, burden of disease has a greater impact.

Adolescent↗

PubMed2006

Improving self-management in insulin-treated adults participating in diabetes education. The role of overprotection by the partner.

AIMS: To examine the role of overprotection by the partner--i.e. excessive protection, unnecessary help, excessive praise for accomplishments, or attempts to restrict activities as a consequence of underestimating the patient's capabilities--in changes in patient self-management in the context of diabetes education. METHODS: Sixty-seven insulin-treated patients with a partner completed questionnaires on admission to a Multidisciplinary Intensive Education Programme (MIEP) and 3 months after completing the core module of MIEP. Factors assessed were overprotection by their partner and three aspects of diabetes self-management, namely internal locus of control, diabetes-related distress and HbA1c. Regression analyses were used to test the independent associations of patient sex, baseline overprotection and the interaction between sex and overprotection with diabetes self-management at the follow-up stage, controlling for the baseline value of the dependent variable. RESULTS: The increase in internal locus of control and decrease in HbA1c were both significantly less for female patients who perceived their partner to be rather overprotective than for female patients who did not perceive their partner to be overprotective. The more patients, both male and female, perceived their partner to be overprotective, the less their diabetes-related distress decreased. CONCLUSIONS: Overprotection by the partner showed a negative association with improvement in diabetes self-management, especially for female patients. Thus, an intervention programme with the aim of reducing overprotection by the partner, or the perception of this, may enhance self-management in patients participating in diabetes education.

Adolescent↗

PubMed2005

Cost and benefits of a multidisciplinary intensive diabetes education programme.

OBJECTIVES: To determine the cost and benefits of an intensive diabetes education programme for patients with prolonged self-management problems and to determine the inclusion criteria for optimal outcomes. METHODS: Sixty-one participants of a multidisciplinary intensive diabetes education programme (MIDEP) were measured before they started the intervention (T0), and at 1-year follow-up (T1). Data on glycaemic control (HbA1c), diabetes-related distress (PAID) and costs were obtained. Changes over time were analysed and means at T0 and T1 were compared to a reference group of 230 non-referred consecutive outpatients. The number needed to treat (NNT), that is, the number of patients to be treated to achieve one successful case, was calculated for different baseline values of HbA1c and PAID to determine optimal inclusion criteria. RESULTS: Diabetes-related costs decreased significantly and participants improved significantly in HbA1c and diabetes-related distress following MIDEP. HbA1c and distress reached the levels of the reference group. The T1 costs remained higher than in the reference group, but the reduction in costs outweighed the intervention costs. Including patients with baseline HbA1c>or=8.0% and/or PAID scores>or=40 would improve the NNT to achieve clinically relevant outcomes, while 76% of the patients matched these inclusion criteria. CONCLUSIONS: MIDEP is effective in improving glycaemic control and diabetes-related distress for patients with prolonged self-management difficulties. Besides the immediate reduction in costs found in the present study, improved glycaemic control may reduce future costs of diabetic complications. Stricter inclusion criteria with respect to HbA1c and PAID scores may further improve the programme's efficiency.

Adult↗

PubMed2004

[Quality of life of patients with occupationally-induced hand eczema].

In recent years quality of life has been studied in a growing number of different dermatological diseases. Internationally validated questionnaires such the RAND-36 (identical to the SF-36) do not contain enough questions which are relevant for skin diseases. There is no publication on quality of life issues in occupational skin diseases, and only one short report gives data on quality of life in hand eczema. The widely used skin specific instrument DLQI has only 2 questions that indirectly refer to employment issues. A quality of life questionnaire on occupational skin diseases (mostly hand eczema) should ideally include questions on work-related impairment of both physical functioning and interaction with colleagues.

Activities of Daily Living↗

PubMed2004

Do diabetologists recognise self-management problems in their patients?

OBJECTIVE: The aim of this study was to determine whether diabetologists recognise patients' needs for additional intensive multidisciplinary care due to glycaemic and diabetes-related psychosocial difficulties. RESEARCH DESIGN AND METHODS: We compared 114 participants in a diabetes intervention programme with 201 as yet non-referred outpatients, of whom 54 outpatients were considered eligible for the intervention by their diabetologists; thus, 147 outpatients were considered non-eligible. RESULTS: Analysis revealed that the eligible patients had poorer glycaemic control but all other parameters were similar to non-eligible patients. Significantly, 22 (15%) of the 147 non-eligible patients clearly had diabetes distress and could potentially benefit from the intervention. CONCLUSION: The results suggest that in regular care, patients' needs with respect to glycaemic control are recognised by their diabetologists, but patients with high psychosocial diabetes-related distress are often overlooked, though they also may be in need of additional care. Integrated monitoring of diabetes-related distress in outpatients could improve this area of diabetes care.

Adult↗

PubMed2001

Morphological analysis of endocytosis in efferent ductules of estrogen receptor-alpha knockout male mouse.

Lack of estrogen receptor (ER) results in fluid accumulation and dilation of the efferent ductules, suggesting that the role of estrogen and ER in the male reproductive tract is related to fluid reabsorption in the ductules. In the present study, endocytosis of the nonciliated cells of the efferent ductules was compared morphologically between wild type (WT) and estrogen receptor-alpha knockout (alpha ERKO) male mice. The epithelial cells lining the WT efferent ductules were tall columnar in shape, whereas those of the alpha ERKO were low columnar. Immunocytochemically, the nonciliated cells of both genotypes showed positive reactions of sulfated glycoprotein-2, but the reaction products were reduced in amount in the alpha ERKO. Electron microscopy revealed that the nonciliated cells of the WT had numerous organelles for endocytosis such as coated pits and vesicles, tubules, endosomes, multivesicular bodies and lysosomes in the apical cytoplasm. These organelles were less developed in the nonciliated cells of the alpha ERKO. Morphometric analysis indicated that there was a significant reduction in area of endocytotic apparatus in the nonciliated cells of the alpha ERKO compared with that of the WT. A tracer study using gold particles demonstrated that the nonciliated cells of both WT and alpha ERKO efferent ductules were capable of taking up luminal contents. These results suggest that reabsorption of the luminal contents via endocytosis takes place in the efferent ductules but is greatly reduced in amount in the absence of ER alpha.

Animals↗

PubMed2001

Comparing the clastogenic potential of atrazine with caffeine using Chinese hamster ovary (CHO) cells.

The agronomically important herbicide atrazine has been reported to cause damage to animal chromosomes at levels of atrazine found contaminating drinking water supplies. While documenting potential chromosome damage is important it is equally important to compare the damage with the potential consequences of compounds readily found in our food and water supply. In this study atrazine and caffeine, a ubiquitous food additive, were compared at equal levels and at real exposure levels for their ability to damage animals chromosomes in cell culture. Nuclei and chromosomes from treated and control cells were analyzed by flow cytometry. At extremely low levels, atrazine was found to be a more potent clastogen. Caffeine had no effect on the chromosomes at the lower levels. Both chemicals were genotoxic at the potential exposure levels with caffeine being more disruptive than atrazine. Atrazine appears to be a more potent damaging agent than caffeine at similar levels of exposure; however, the levels of caffeine one is exposed to during everyday life appears to be more damaging on the endpoints analyzed in this study than the levels of atrazine found contaminating water supplies. The advantages and limitations of whole cell clasotgenicity are also presented in light of these results.

Animals↗

PubMed2001

How to validate clinically important change in health-related functional status. Is the magnitude of the effect size consistently related to magnitude of change as indicated by a global question rating?

Some clinical trials perform repeated measurement over time and estimate clinically relevant change in an instrument's score with global ratings of perceived change or so-called transition questions. The conceptual and methodological difficulties in estimating the magnitude of clinically relevant change over time in health-related functional status (HRFS) are discussed. This paper investigates the concordance between the amount of serially assessed change with effect size estimates (the researcher's perspective) and global ratings of perceived change (the patient's perspective). A total of 217 patients who were scheduled for diagnostic examination were included, and the Minnesota Living with Heart Failure Questionnaire, extended with MOS-20 items, was assessed before and after medical intervention (percutaneous transluminal coronary angioplasty, coronary artery bypass grafting or pharmaco-therapy). Global questions were applied to assess perceived change over time for every item from domains of physical and emotional functioning and used as the external criterion of relevant change in the analysis of items. Global questions corresponding with overall change in these domains were used in the comparison of change in physical and emotional functioning scales. Two effect size indices were used: (i) ES (mean change/SDpooled) and (ii) ES (mean change/SDchange). A method is described to calculate a value indicating the extent of discordance between the researcher's interpretation of magnitude of change and the external criterion (the patient's perspective). Findings suggest that effect size (ES) (mean change/SDpooled) was in keeping with the magnitude of change indicated by patients' judgements, or their category of subjective meaning, for all scales. Furthermore, in cases in which the magnitude of change estimated with the SRM (mean change/SDchange) was not confirmed empirically by the external criterion ratings, the discordance could be interpreted as a trivial discordance.

Activities of Daily Living↗

PubMed2001

Estrogen receptor-alpha protein localization in the testis of the rainbow trout (Oncorhynchus mykiss) during different stages of the reproductive cycle.

Estrogen receptor-alpha (ER-alpha) is important for male reproduction in mammals; however, no information is available on ER-alpha protein distribution in the testes of fishes. The cellular localization of the rainbow trout (Oncorhynchus mykiss) ER-alpha (rtER-alpha) protein, throughout the annual reproductive cycle was determined in this study. An antibody was designed based on a 15-amino acid sequence from the D-domain of the rtER-alpha, and its specificity was confirmed using Western blot analysis. Immunohistochemical analysis revealed rtER-alpha protein to be present only in the testicular interstitium, at every stage of the annual reproductive cycle. The localization of rtER-alpha protein in the interstitial fibroblasts, the Leydig cell precursor in the rainbow trout, suggests a role for estrogens in the differentiation of these precursor cells into mature Leydig cells. This is the first study to report the cellular localization of an estrogen receptor protein in the testis of any fish species.

Amino Acid Sequence↗

PubMed2001

Psychometric properties of the Minnesota Living with Heart Failure Questionnaire (MLHF-Q).

OBJECTIVE: To evaluate the psychometric properties of the Minnesota Living with Heart Failure Questionnaire (MLHF-Q) in patients with atrial fibrillation. DESIGN: A prospective study of the patients who underwent DC electrical cardioversion. SETTING: Clinics of cardiology and thoracic surgery of the University Hospital in Groningen, the Netherlands. MAIN OUTCOME MEASURES: The disease-specific MLHF-Q and generic measures of quality of life were administered. The sensitivity to change over time was tested with effect sizes (ES). Internal consistency of MLHF-Q scales was estimated with Cronbach's alpha. To evaluate the construct validity multitrait-multimethod analysis was applied. The 'known group validity' was evaluated by the comparison of mean scores and effect sizes between two groups of the New York Heart Association (NYHA) classification (NYHA I versus II-III). Stability of MLHF-Q scales was estimated in a subgroup of patients who remained stable. Perfect congruence analysis and factor analysis were applied to confirm the a priori determined structure. RESULTS: Cronbach's alpha was > or = 0.80 of the MLHF-Q scales. Perfect congruence analysis (PCA) showed that the results resemble quite well the a priori assumed factor structure. Multitrait-multimethod analysis showed convergent validity coefficients ranging from 0.59 to 0.73 (physical impairment dimension) and 0.39 to 0.69 (emotional dimension). The magnitude of change can be interpreted as medium (ES = 0.50). The results of a 'test-retest' analysis in a stable group can be valued as satisfactory for the MLHF-Q scales (Pearson's r > 0.60). The physical dimension and the overall score of the MLHF-Q discriminated significantly between the NYHA I and II-III groups (p < 0.001) with large effect sizes (ES > 1.0).

Adult↗

PubMed2001

High incidence of a male-specific genetic marker in phenotypic female chinook salmon from the Columbia River.

Numerous populations of anadromous salmonids in the northwestern United States have been declining for many years, resulting in Endangered Species Act listings and in some cases extinction. The degradation of river ecosystems has been proposed as one of the major reasons for the inability of salmon to maintain their populations. However, the specific factors interfering with the reproduction and survival of salmon during the freshwater phase of their life cycle have not been fully described. This study was initiated to determine the incidence of phenotypic sex reversal in wild, fall chinook salmon (Oncorhynchus tshawytcha) that returned to spawn in the Columbia River. Fish were sampled at different locations within this watershed to determine whether they were faithfully expressing their genotype. We report a high incidence (84%) of a genetic marker for the Y chromosome in phenotypic females sampled from the wild, which was not observed in female fish raised in hatcheries. It appears likely that female salmon with a male genotype have been sex reversed, creating the potential for an abnormal YY genotype in the wild that would produce all-male offspring and alter sex ratios significantly.

Animals↗

PubMed2000

[Regional differences in prehospital time delay for patients with acute myocardial infarction; Rotterdam and Groningen, 1990-1995].

OBJECTIVE: To describe pre-hospital delay times in patients with acute myocardial infarction (AMI) in two regions in the Netherlands: Groningen (a region with high mortality for coronary heart disease (CHD)) and Rotterdam (a region with low CHD mortality). DESIGN: Descriptive. METHOD: The pre-hospital treatment delay of AMI patients in Rotterdam in 1990-1991 versus 1993-1995 was compared and also compared between Groningen en Rotterdam (1993-1995). In each region 3 hospitals participated (1 academic, 2 regional). The data were collected with a structured interview within 7 days after onset of symptoms in hospitalized AMI patients (n = 924) or by interviewing relatives of deceased patients (n = 40). The median patient, general practitioner (GP) and ambulance delays were calculated. RESULTS: Total median pre-hospital delay was 2.5 hours (5-95-percentile: 50 min-36 hours). Median patient delay time was shorter in Groningen than in Rotterdam (respectively 30 and 45 min) and the same applied to doctor delay times (respectively 38 and 72 min). In Rotterdam doctor delay time decreased by 23 min between 1990-1991 and 1993-1995. Median ambulance delay was 30 min in Rotterdam and 35 min in Groningen. Total pre-hospital delay times of self referred patients were 32-78 min shorter than those of patients who consulted a GP before admission. CONCLUSION: Reduction of pre-hospital delay in Rotterdam between 1990-1991 and 1993-1995 was due to faster decision time by the GP. The short pre-hospital treatment delay in Groningen in hospitalized patients suggests that relatively more AMI patients die outside hospital which may contribute to the high CHD mortality in this region.

Emergency Medical Services↗

PubMed1999

Immunohistochemical localization of somatostatin receptor sst2A in sarcoid granulomas.

BACKGROUND: In a previous study, we demonstrated the presence of receptors for somatostatin, a neuropeptide with immunoregulatory properties, in the inflammatory lesions of patients suffering from sarcoidosis and other granulomatous diseases by in vivo somatostatin receptor scintigraphy and in vitro autoradiography. However, it was not possible to identify exactly which cell types expressed the somatostatin receptors and which subtype was expressed. In this study we used a polyclonal antiserum directed against the sst2A receptor to identify more accurately the sst2A-expressing cells in sarcoidosis and other granulomatous diseases. DESIGN: Tissue biopsies from 12 patients with sarcoidosis, one patient with giant cell arteritis and one patient with Wegener's granulomatosis were studied by immunohistochemistry with the sst2A-specific antiserum. Two of the sarcoidosis patients were treated with the somatostatin analogue octreotide (100 microg t.i.d.). RESULTS: Epithelioid cells, multinucleated giant cells and a subset of CD68+ macrophages stained positive for sst2A in 9 out of 12 of the sarcoid biopsies and in both non-sarcoid granuloma biopsies. Treatment with octreotide resulted in clinical improvement in one out of two treated patients. CONCLUSION: The identification of somatostatin receptors on granuloma macrophages, epithelioid cells and giant cells, and the successful treatment of one patient with sarcoidosis with a somatostatin analogue, may offer new possibilities for treatment of granulomatous diseases.

Adult↗

PubMed1999

Longer pre-hospital delay in acute myocardial infarction in women because of longer doctor decision time.

STUDY OBJECTIVE: To measure the pre-hospital delay times in patients with proven acute myocardial infarction (AMI) and to identify possibilities for reduction of treatment delay. DESIGN: Descriptive three centre study. SETTING: One university teaching hospital and two regional hospitals in Groningen, the Netherlands. PATIENTS: 400 consecutive confirmed AMI patients, age below 75 years, admitted to coronary care departments. MAIN RESULTS: Mean age was 59 years and 78% of patients were men. Within two hours after onset of symptoms half of the patients with AMI arrived at the hospital. Patient, doctor, and ambulance delay times (median values) were 30, 38, and 35 minutes respectively. Calling the personal general practitioner (GP) or the locum tenens and whether or not the AMI occurred during a weekend or on a working day had no consequences for pre-hospital delay times. At night patients waited longer before calling a GP than in the daytime. There was a positive correlation between patient and doctor delay. Twenty two per cent of AMI patients waited two hours or more before calling a GP. Total pre-hospital delay times differed between men and women. Longer doctor delay in women (36 minutes for men and 52 minutes for women) was caused by displacement of specific symptoms, in particular in women. AMI patients who were alone during onset of symptoms showed higher patients delay (72 compared with 23 minutes). CONCLUSION: In hospital admitted patients younger than 75 years pre-hospital delay times are within acceptable limits. In some subgroups further reduction is attainable, for example in patient delay outside office hours and when patients are alone during onset of symptoms, in doctor delay in cases where women present with symptoms suggestive for AMI. Improvement of facilities for pre-hospital electrocardiographic diagnosis may facilitate decision making by GPs. Good opportunities for further reduction of treatment delay exist in shortening of hospital delay.

Acute Disease↗

PubMed1999

Cost analysis of the treatment of severe spinal spasticity with a continuous intrathecal baclofen infusion system.

OBJECTIVE: The purpose of our study was to analyse and evaluate the costs of continuous intrathecal baclofen administration as a modality in the treatment of severe spasticity in the Netherlands. DESIGN: A cost analysis was conducted as part of a prospective, multicentre, multidisciplinary, randomised and placebo-controlled clinical trial. The study covered the period from December 1991 to September 1995. The data on medical consumption and costs were collected over a 3-year period from different sources: administrative databases of health insurance companies, hospital registries and a patient survey. These data were structured by means of a flowchart analysis of the medical decision-making by specialists and general practitioners (GPs). They included data on in- and outpatient care, home care and care in nursing homes. The cost analysis was conducted using data from 18 patients included in the trial and from 15 so-called 'match' patients. The latter group are patients with comparable diseases leading to spasticity and living in comparable circumstances. Next to absolute costs (direct and indirect) of care and treatment for the 2 groups of patients, cost differences between the 2 groups were considered (differential cost analysis). SETTING: Per patient cost data, collected prospectively for 2 years during the phase of clinical evaluation, and retrospectively 1 year before implantation. The data were collected on patients from in- and outpatient care, home care and care in nursing home settings. PATIENTS AND PARTICIPANTS: The trial patients (8 men) had a mean age of 46 years; 11 patients had multiple sclerosis and 7 patients had spinal cord injuries. The match patients (7 men) had a mean age of 48 years; 9 patients had multiple sclerosis and 6 patients had spinal cord injuries. INTERVENTIONS: Trial patients were treated with a subcutaneously implanted programmable continuous infusion pump (SynchroMed, Medtronic), filled with baclofen (a muscle relaxant) to treat patients with chronic disabling spasticity who did not respond to a maximum dose of oral baclofen, dantrolene and tizanidine. MAIN OUTCOME MEASURES AND RESULTS: An analysis of hospital stay between both groups showed a significant difference during the implantation year. The average number of hospital days per patient in the year in the treated group was 31.5 days and in the match group was 18.7 days. Significant cost differences between both groups in the year that started with pump implantation and the following year can be attributed mostly to the costs of implantation of the pump and related hospitalisation days. The total costs of patient selection, testing, implanting the pump and follow-up amounted to $US28,473 for the first year. Savings must be taken into consideration as well. The savings of direct costs were due to withdrawal of oral medication (estimated annual total of between $US1950 and $US2800 per patient). Indirect savings on employment and nursing home costs, amounted annually to $US1047 and $US5814, respectively. Scenarios make it possible to consider policy consequences. The case of 'extending' the indications for this treatment to a larger population has been calculated and visualised. CONCLUSIONS: The costs of the therapy (continuous intrathecal infusion of baclofen) can be attributed mostly to implantation of the pump and related hospitalisation days. Savings originated from withdrawal of oral medication, job preservation and avoidance or delay of admission to a nursing home.

Adult↗

PubMed1998

The stability of lifestyle behaviour.

BACKGROUND: The stability of lifestyle behaviour has been studied over a 4-year period in a sample of 1400 men in The Netherlands. The influence of both socioeconomic status and age was studied in relation to lifestyle behaviour change. METHODS: Lifestyle behaviour was analysed by means of index scores, each covering one of four domains: smoking, alcohol consumption, physical activity and dietary habits. Changes in lifestyle behaviour were analysed at individual and group level, using different statistical methods. RESULTS: Smoking behaviour remained highly constant, whereas alcohol consumption had only moderate stability. Physical activity and dietary habits had greater variability over this time period. Age and socioeconomic status are related to the prevalence of lifestyle behaviour, whereas only age is related to the stability of lifestyle behaviour. Socioeconomic status did not relate to changes in lifestyle behaviour. CONCLUSIONS: The four lifestyle behaviours differed in the degree of variation over a 4-year period. Only a small group (11%) changed two or more lifestyle behaviours. This implies that lifestyle behaviour is not a unified concept and should not be treated in that way in public health campaigns.

Adult↗

PubMed1997

Precision agriculture: introduction to the spatial and temporal variability of environmental quality.

Precision agriculture aims at adjusting and fine-tuning land and crop management to the needs of plants within heterogeneous fields. Production aspects have to be balanced against environmental threshold values and modern information technology has made it possible to devise operational field systems. A reactive approach is described, using yield maps and sensors. A proactive approach uses simulation modelling of plant growth and solute fluxes to predict optimal timing of management practices. Precision agriculture, combining both approaches, is seen as making a major contribution towards the development of sustainable agricultural production systems.

Agriculture↗