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The Southern Medical Association is accredited by the Accreditation Council for Continuing

CME Article of the Month

Southern Medical Association

CME CREDIT

Date of Original Release:February 2000

Term of Approval: 1 Year

The Southern Medical Association is accredited by the Accreditation Council for Continuing Medical Education to sponsor continuing medical education for physicians. The following article was designed for physicians in all specialties, especially those in primary care, and the estimated time for completion is 1 hour. This CME activity was planned and produced in accordance with the ACCME Essentials. The Southern Medical Association designates this continuing medical education activity for 1 credit hour in Category 1 of the Physician’s Recognition Award of the American Medical Association. The CME Article of the Month is a CME activity developed and administered by the Southern Medical Association’s Department of Education. To obtain Category 1 credit, follow the instructions at the end of the article.

PURPOSE AND OBJECTIVES

Dizziness accounts for an estimated 7 million clinic visits in the United States each year, and it is a chal-lenging symptom to evaluate and manage. Physicians in all specialties, especially those in primary care, have a crucial role to play in the evaluation and treatment of dizziness. After reading this article, physi-cians should be able to enumerate the common and uncommon causes of dizziness, to use this infor-mation to assist in formulating a differential diagnosis, and to implement a practical approach to pro-vide optimal evaluation of the dizzy patient.

DISCLOSURE

In publishing this article in Southern Medical Journal,the Southern Medical Association recognizes edu-cational needs of physicians in all specialties, especially those in primary care, for current information regarding dizziness. In this article, authors may have included discussions about drug interventions, whether Food and Drug Administration approved or unapproved. Therefore, it is incumbent on physi-cians reading this article to be aware of these factors in interpreting the contents and evaluating recom-mendations. Moreover, views of authors do not necessarily re?ect the opinions of the Southern Medical Association. Every effort has been made to encourage the author to disclose any commercial relation-ships or personal bene?t that may be associated with this article. If the author disclosed a relationship, it is indicated below. This disclosure in no way implies that the information presented is biased or of lesser quality.

Kurt Kroenke, MD

Grant/Research Support:

Consultant:

Speaker’s Bureau:

Stock Shareholder:

Other Support:

DISCLAIMER

The primary purpose of this article in the Journal is education. Information presented and techniques discussed are intended to inform physicians of medical knowledge, clinical procedures, and experi-ences of physicians willing to share such information with colleagues. It is recognized that a diversity of professional opinions exists in the contemporary practice of medicine that in?uences the selection of methods and procedures. The views and approaches of authors are offered solely for educational pur-poses. The Southern Medical Association disclaims any and all liability for injury or other damages to any individual reading this article and for all claims that may result from the use of techniques and pro-cedures presented in it.

Kroenke et al?CAUSES OF DIZZINESS159

D IZZINESS accounts for an estimated 7 million clinic visits in the United States each year1and is one of the most common symptoms referred to neurology and otolaryngology practices. Several factors make dizziness a challenging symptom to evaluate and manage. First, pre-cise classi?cation of the cause is often dif?cult. Second, worry about a cardiac or neurologic cause (dysrhythmia, cerebrovascular ischemia, or brain tumor) that if missed could be serious and even fatal may concern the patient and clinician alike. Third, speci?c therapy is not available for many patients with dizziness. Considerable literature has been written on dizziness, including textbooks,2-4but much of this discusses speci?c vestibular causes and the role of vestibular function testing. Surprisingly, the frequency of various causes of dizziness in series of consecutive patients has been the focus of only a handful of studies; no pub-lished critical review synthesizes the ?ndings.

Thus, we conducted a systematic review of the available literature on the etiology of dizzi-ness in consecutive patients evaluated for this complaint. Our major aim was to provide an estimate of how common various causes of diz-ziness actually are, information that should be useful in the initial assessment of the dizzy pa-tient and to decisions about the potential util-ity and sequencing of diagnostic testing. METHODS

Literature Search

We searched the MEDLINE database from 1966 through 1996 to identify articles with the MeSH headings dizziness or vertigo. These headings were combined with the subhead-ings epidemiology, classi?cation, diagnosis, and eti-ology. Articles were also identi?ed from bibli-ographies of review articles and retrieved articles. Two investigators independently eval-uated titles and abstracts and reached consen-sus on which articles to retrieve.

A major criterion for inclusion in this review was that the study reports on patients present-ing any complaint of dizziness, regardless of symptom character. Studies focusing only on patients with vertigo (ie, studies that excluded patients with nonvertiginous dizziness) or in-

How Common Are Various Causes of Dizziness? A Critical Review

KURT KROENKE, MD, Indianapolis, Ind; RICHARD M. HOFFMAN, MD, MPH, Albuquerque, NM; and DOUGLAS EINSTADTER, MD, MPH, Cleveland, Ohio

A BSTRACT

Background. Although dizziness is a common symptom in both primary care and referral practices, the relative frequency of various causes has not been well delineated.

Methods. A MEDLINE search identi?ed 12 articles containing original data on the etiology

of dizziness in consecutive patients. Study sites included primary care of?ces (n = 2),

emergency room (n = 4), and referral clinics (n = 6). Each study’s strength of design was

graded using nine quality criteria.

Results.Dizziness was attributed to a peripheral vestibulopathy in 44% of patients, a central vestibulopathy in 11%, psychiatric causes in 16%, other conditions in 26%, and an unknown

cause in 13%. Certain serious causes were relatively uncommon, including cerebrovascular disease (6%), cardiac arrhythmia (1.5%), and brain tumor (<1%).

Conclusions.Dizziness is due to vestibular or psychiatric causes in more than 70% of cases.

Since serious treatable causes appear uncommon, diagnostic testing can probably be reserved

for a small subset of patients.

160February 2000?SOUTHERN MEDICAL JOURNAL?Vol. 93, No. 2

vestigations limited to speci?c types of dizzi-ness (benign positional vertigo, Meniere’s dis-ease, etc) were excluded, since our purpose was to estimate the frequency of various causes in “all comers” with dizziness. Other inclusion criteria were English-language publication, original study data, sample size ≥10 patients, and patients aged ≥18 years. Data were ab-stracted from each study by two investigators, with differences resolved by the third investi-gator.

We found a total of 12 studies involving 4,536 patients that met our inclusion criteria: 2 primary-care based studies,5,64 studies from emergency room populations,7-10and 6 refer-ral-based studies.11-16All 12 studies reported on consecutive patients seeking evaluation of a chief complaint of dizziness. Four of these studies focused exclusively on older patients, either elderly13,16or middle-aged14,15individuals. Ten of the studies had roughly similar sample sizes of about 100 patients (range, 93 to 140), whereas two studies involved much larger numbers of patients (2,222 and 1,194, respec-tively).12,13Quality Rating of Studies

Study quality was assessed with points (maxi-mum score = 13) assigned as follows:

(1) Was the sample primary care based? (0 = no, 1 =

predominantly, 2 = exclusively).

(2) Was this an inception cohort, ie, patients pre-

senting with their ?rst episode of dizziness? (0 = no,

1 = yes)

(3) Was the sampling consecutive or random (rather

than convenience sampling or not described) to

minimize selection bias? (0 = no; 1 = yes)

(4) Was the study design prospective rather than ret-

rospective? (0 = no; 1 = yes)

(5) Were patients evaluated with a standard proto-

col? (0 = no; 1 = yes)

(6) Did patients have formal vestibular testing? (0 =

no or minority of patients; 1 = selected cases but

≥50% of patients; 2 = neuro-otologic clinical exami-

nation by trained specialist in all cases; 3 =

electronystagmography or other objective vestibular

function test in all patients)

(7) Did patients have formal psychiatric testing? (0 =

no; 1 = psychometric tests; 2 = structured psychiatric

interview)

(8) Did the investigators report the explicit criteria

they used in assigning patients to speci?c etiologic

categories? (0 = no; 1 = yes)

(9) Were multiple raters used in classifying patients,

rather than a single investigator reviewing the data

and assigning causes? (0 = no; 1 = yes)

Criteria were derived in part from epidemio-logic principles underlying the design of rigor-ous studies of diagnosis and causation17-19and in part from the especially common causes of dizziness (vestibular and psychiatric) that may be dif?cult to accurately diagnose in some pa-tients without specialized evaluation. Thus, the extent of vestibular and psychiatric testing re-ceived special weighting (maximum of 3 points each), as did the primary care nature of the sample (2 points) in the overall quality rat-ing scheme.

Classi?cation of Causes

In this paper, we report our results using diagnostic classifications drawn from the 12 studies. Peripheral vestibular causes include be-nign positional vertigo, labyrinthitis (or vestibu-lar neuronitis), Meniere’s disease, and other less common disorders (drug-related ototox-icity) or nonspeci?c disorders (peripheral ves-tibulopathy of uncertain cause). Central vestibu-lar causes include cerebrovascular disease (strokes or transient ischemic attacks [TIAs]); brain tumors (acoustic neuromas or less com-monly cerebellar or other posterior fossa tu-mors); and other central vestibular disorders, such as multiple sclerosis, migraine, or dizziness

Kroenke et al?CAUSES OF DIZZINESS161

with ?ndings indicative of a central vestibulopa-thy on neuro-otologic or vestibular testing. Psychiatric causes refer to those cases investiga-tors attribute to psychologic factors, typically in the absence of evidence of nonpsychiatric causes. Hyperventilation is included in this cat-egory because of evidence that the underlying cause is probably panic disorder or another anxiety disorder, but for studies in which hyper-ventilation is reported separately, we present these data. Presyncope comprises dizziness due to decreased perfusion, typically orthostatic hypo-tension, arrhythmias, or other cardiovascular causes. Dysequilibrium refers to unsteadiness or balance disorders, most commonly in the el-derly as described. Other causes of dizziness in-clude anemia, metabolic causes (hypoglycemia or hyperglycemia, electrolyte disturbances, thy-roid disease, etc), medication-related (exclud-ing those cases in which the insult is a vestibu-lopathy, such as aminoglycoside toxicity), nonvestibular neurologic causes (Parkinson’s disease), and less common causes not included in the speci?c categories previously de?ned. Unknown cause refers to those cases of dizziness in which a cause cannot be assigned after diag-nostic evaluation had been completed. Analysis

In combining data from studies to arrive at summary measures, we used the study (rather than total patients) as the unit of analysis for several reasons. Major differences among stud-ies in terms of type of patient population and extent of diagnostic evaluation would make pooling patients inappropriate. If patients had been pooled, the two largest studies compris-ing 3,416 (75%) of the patients would have dominated the analysis; yet, these two studies had only moderate to poor quality ratings of 5 and 2.12,13

Three summary statistics for each of the eti-ologic categories were calculated: range of fre-quencies among the 12 studies; median fre-quency; and quality-adjusted mean frequency. The latter was a method for assigning greater weight to higher quality studies by multiplying a particular study’s mean by the square root of its quality rating. The resulting weighted means of the 12 studies for a particular causal category (peripheral vestibulopathy) were added together and this sum was divided by the sum of the adjusted quality scores. This square root adjustment allowed modest weight-ing for high-quality studies (ie, less weighting than the use of simple untransformed quality scores would have provided but more weight-ing than a logarithmic transformation).20 RESULTS

Quality of Studies

Table 1 shows the number of studies that satis?ed each of the nine quality criteria. All studies had a sampling scheme where consec-utive patients presenting with dizziness were eligible for participation. Half of the studies were prospective. No study speci?cally claimed to involve an inception cohort consisting ex-

162February 2000?SOUTHERN MEDICAL JOURNAL?Vol. 93, No. 2

clusively of patients presenting with their ?rst episode of dizziness. A minority of the investi-gators published the explicit criteria they used to assign etiology, and only one study incorpo-rated a structured interview to make criteria-based psychiatric diagnoses or used multiple raters to classify patients.

Quality scores (which could range from 0 to 13) of the individual studies varied consider-ably. Two studies had relatively high scores of 105or 811;seven studies had intermediate scores of 6,15,165,7,12,14or 46,8; and three had low scores of 29,13or 1.10

Frequency of Speci?c Causes

Table 2 lists the frequency of speci?c causes of dizziness. Peripheral vestibular causes are the most common, with 16% of cases being due to benign positional vertigo, 9% due to labyrinthi-tis, and 5% due to Meniere’s disease. Although other less common causes of a peripheral vestibular disorder were occasionally noted (drug-induced ototoxicity), the remainder were most often a nonspeci?c vestibulopathy. Cerebrovascular disease accounted for 6% of cases of dizziness. All except two studies10,14 further characterized the cause as either stroke or TIA. In the 10 studies that distin-guished between these two types of cere-brovascular events, dizziness was attributed to stroke in 2.9% (range, 0% to 10%) and TIA in 2.6% (range, 0% to 10%) of patients.

Brain tumor was detected in 32 patients (0.7% of the 4,536 patients assessed); seven studies reported one or more cases,6,8,12-16where-as ?ve studies reported no tumors. Although several studies did not specify the tumor type, it appears that the majority were acoustic neu-romas. The studies did not present data on how many of the patients with brain tumors had abnormal hearing or neurologic de?cits on history or physical examination.

Other central vestibular causes were re-ported in 57 patients (1.2%), including 18 pa-tients with abnormal examination findings (vertical nystagmus, abnormal brain stem evoked potentials) without a speci?c diagno-sis, 17 with cerebellar atrophy, 7 with mi-graine, 6 with multiple sclerosis, 3 with epilep-sy, and 6 with other diagnoses.

Presyncope was considered the cause in 6% of patients. All except two studies6,10provided suf?cient data to determine whether the pre-syncope was due to a cardiac arrhythmia or a less serious disorder (most commonly, volume depletion or other type of orthostatic hypoten-sion). In the 10 studies making this distinction, dizziness was attributed to a cardiac arrhythmia in 1.5% (range, 0% to 5%) and noncardiac causes in 4.1% (range, 0% to 13%). Dizziness was due to psychiatric disorders (including hyperventilation) in 16% of pa-tients, dysequilibrium in 5%, and other causes (medications, metabolic disturbances, infec-tions, trauma, etc) in 16%. Finally, the cause remained unknown in 13% of patients. Effect of Study Design on Frequencies

Table 3 shows the effect of clinical site, pa-tient age, and quality of vestibular and psychi-

Kroenke et al?CAUSES OF DIZZINESS163

atric testing on the frequency of major cate-gories of dizziness. All other in this Table in-cludes patients classified as having presyn-cope, dysequilibrium, or other causes listed in Table 2.

Peripheral vestibular disorders accounted for one third to one half of all cases across all four types of clinical sites. Three of the four studies that did not use vestibular testing origi-nated from emergency rooms and had the lowest proportion of cases diagnosed as peripheral vestibular. Central vestibular causes were more common in neurology clinic and older patients; which factor is most important cannot be determined because of overlap, ie, 3 of the 4 studies limited to older patients were the 3 neurology clinic studies.

Finally, the extent of testing may affect diag-nostic classi?cation: studies that incorporated formal vestibular or psychiatric testing had a higher proportion of patients with diagnoses of vestibular and psychiatric causes of dizzi-ness. This was particularly striking for psychi-atric causes, which accounted for 30% of the cases of dizziness in the two studies that used formal psychiatric testing but only 11% of cases in studies that did not use such testing. Uncommon or Controversial Causes

The total number of cases of selected causes of dizziness was determined from 10 of the 12 studies; 2 studies10,12did not provide data that allowed exact classification of every case. In these 10 studies representing 2,208 dizzy pa-tients, hyperventilation was considered the cause in 47 (2.1%), anemia or other metabolic causes in 24 (1.1%), cervical arthritis in 10 (0.4%), multiple sclerosis in 6 (0.3%), visual disturbances in 6 (0.3%), migraine in 3 (0.1%), perilymphatic ?stula in 2 (0.1%), and disabling positional vertigo in no patients. Hyperventilation was a common cause in only one study; moreover, Drachman and Hart11reported that in 15 of the 24 cases classi-?ed as hyperventilation, the patients also had “signi?cant psychiatric disorders.” This same study was the only one that attributed even a single case of dizziness to cervical arthritis; moreover, cervical arthritis was not the sole cause in any patient in this study but rather only one of the contributing factors in 10 pa-tients with a diagnosis of multisensory dysequi-librium.

DISCUSSION

Despite the frequency of dizziness in both primary care and referral settings, we found only 12 studies of etiology in consecutive dizzy patients. Dizziness may be vestibular in etiol-ogy more than half of the time, whereas psy-chiatric disorders are the second most com-mon cause. Serious causes are found in a small minority of patients, and no cause is estab-lished in 1 of 7 cases.

The infrequency of serious causes is reassur-ing. Brain tumors are an uncommon diagnosis in patients with dizziness. Since most are acoustic neuromas, cochlear symptoms (tinni-tus and hearing loss) are typically prominent. Cerebrovascular disease was on average the re-ported cause of dizziness in 6% of patients, about one half of whom have actual strokes and the other half have TIAs. In vertigo of vas-cular origin, dizziness has been reported as the presenting symptom <20% to 25% of the time.21,22Much more commonly, it is preceded or accompanied by other neurologic de?cits.

164February 2000?SOUTHERN MEDICAL JOURNAL?Vol. 93, No. 2

Additionally, vertigo typically represents poste-rior circulation ischemia, for which revascular-ization is usually not a management option. Even diagnosing a TIA as the cause of vertigo can be dif?cult in the absence of other neuro-logic de?cits, since isolated vertigo is nonspe-cific and there is no good noninvasive diagnos-tic test of the vertebrobasilar circulation. Cardiac arrhythmias are likewise the cause of dizziness in a small proportion (1% to 5%) of patients, though most protocols did not include Holter or event monitoring. The few studies that have examined the utility of a sim-ple electrocardiogram (ECG)5,7,9or, in one small series, ambulatory ECG monitoring23 have suggested a low yield of cardiovascular testing in diagnosing the dizzy patient. Thus, testing for cardiac causes seems less important in working up dizziness without syncope than in the evaluation of true syncope.

Some causes conventionally included in the differential diagnosis of the dizzy patient were exceedingly uncommon, and several others are controversial. Hyperventilation was com-monly diagnosed in only one study and, even in this one, the majority of patients with a diagnosis of presumed hyperventilation also had significant psychiatric disease.11 Hyper-ventilation appears to be a nonspecific pro-vocative maneuver,5,24and many of the patients can be diagnosed as having panic disorder or another anxiety disorder.25-27Cervical arthritis was not reported as a sole cause of dizziness in any patient and, indeed, there are no estab-lished criteria for a diagnosis of “cervical ver-tigo.” Dizziness as a manifestation of a visual disorder was also seldom reported. Vertigo is said to be the initial symptom in 5% of pa-tients with multiple sclerosis, ultimately occur-ring in up to 50%.28,29In series of dizzy pa-tients, however, multiple sclerosis seems to be a rare cause. Vertigo can accompany about 30% of migraine headaches and may occur as an aura or a separate event.30However, iso-lated vertigo as a migraine variant (acephalgic migraine) is controversial and was seldom diagnosed in the studies we reviewed. Except for a small number of patients in two emer-gency room studies, anemia or metabolic causes of dizziness were also seldom detected. Two other diagnoses, important in that they may sometimes prompt surgical intervention, were seldom (perilymph ?stula) or never (dis-abling positional vertigo) reported in the series reviewed. There is no pathognomonic test for perilymph fistula, and its frequency and precise diagnosis remains controver-sial.2,4.31Since there is no agreed upon way to con?rm a perilymph ?stula short of surgical exploration, it is possible that it was under-diagnosed. Disabling positional vertigo due to neurovascular compression of the eighth cra-nial nerve has really been regularly reported by only one group of investigators.32,33

Given that no cause is established in 1 of every 7 dizzy patients, an important question concerns the subsequent course of patients with “idiopathic” dizziness: do their symptoms improve, persist, or serve as early indicators of a speci?c disorder that will eventually manifest itself? Only one of the studies5published infor-mation on later outcomes, and in this study idiopathic dizziness was not associated with an increased risk of chronic symptoms or serious occult disease.34However, the numbers of patients were small, and clearly more studies on prognosis are needed.

Methodologic problems (Table 1) clearly limit the generalizability of the etiologic studies and, coupled with differences in the patient populations examined, probably account for some of the wide variability in frequency of spe-ci?c causes. Although the actual scores we used in assessing study quality are slightly arbitrary, the criteria themselves (Table 1) identify some important study design issues in evaluating the etiology of dizziness. The prospective investiga-tion of a consecutive sample of primary care patients using a standard protocol helps assure uniform and consistent evaluation with the least amount of selection bias, but only one study5 used this design. While vestibular func-tion testing and structured psychiatric inter-views are essential to accurately diagnose the two most common causes of dizziness, only two studies5,11systematically tested for both vestibu-lar and psychiatric diagnoses. Finally, the ex-plicit criteria investigators used to classify cases were reported in only 4 of the 12 studies, a dis-appointing omission considering the potential subjectivity that can occur in classifying dizzy patients. Also, the criteria used need to be re-ported if other researchers in different settings are to compare frequencies of various causes. Only one study used multiple raters to inde-pendently review data and classify patients.5 Interobserver agreement among the three raters was only modest (?of 0.39), possibly be-cause a single “pure” cause was assigned to only 52% of patients, while in the other half two or more factors were believed to be causative or contributory. Since all three raters reviewed the

Kroenke et al?CAUSES OF DIZZINESS165

identical data from each patient abstracted onto a uniform study form (rather than pour-ing through charts) and applied explicit crite-ria, this study should have maximized agree-ment. Substantial clinical disagreement has been documented in many areas of medi-cine,35,36and dizziness as a complex and subjec-tive complaint may be particularly susceptible to classi?cation disagreement.5Studies that rely on one clinician rather than a consensus pro-cess to determine cause could be biased by the diagnostic preferences of a single rater.

No study used an inception cohort of pa-tients having their first episode of dizziness. This can be dif?cult since dizziness, like other common symptoms such as back pain and headache, is often an episodic symptom. Pa-tients presenting themselves for evaluation may have had dizziness in the past for which they either did not seek care or, if they did see a clinician, were not given a diagnosis. One might speculate that a pure inception cohort might include more patients with minor or temporary causes of dizziness (viral infections, medication-related causes, volume depletion) or self-limited idiopathic reasons for their symptoms; these were common factors in pa-tients whose dizziness resolved quickly in one outcome study.34However, a true inception co-hort would be required to better de?ne the causes and natural history of dizziness in per-sons having their ?rst episode.

Type of clinic, patient age, and the extent of vestibular and psychiatric testing were associ-ated with the relative frequency of various major causes (Table 3). Studies that looked more systematically for vestibular and psychi-atric disorders indeed found more patients with these disorders as the cause of their dizzi-ness. However, 3 of the 4 studies not incorpo-rating vestibular testing were done in emer-gency room populations; it is unclear whether the lack of testing or a different type of patient accounted for a lower frequency of vestibular causes. Central vestibular causes were more common in elderly samples, but this ?nding was likewise confounded by the fact 3 of the 4 studies that were limited to older patients emanated from neurology clinics.

Since few studies were primary-care based, we cannot draw precise conclusions about the frequency of various causes of dizziness in uns-elected patients in the general medical setting. One population-based study by Colledge et al37 was not included because it drew upon per-sons experiencing dizziness in the community rather than patients presenting themselves for care, and because certain causes claimed to be common were de?ned in a unique and atypi-cal fashion.

What are the implications for diagnostic test-ing in evaluation of the dizzy patient? Simple history and physical examination are usually suf?cient for some of the more common causes (benign positional vertigo, labyrinthitis, ortho-static hypotension, depressive and anxiety disor-ders). For patients with persistent undiagnosed dizziness, vestibular function testing and screening for common mental disorders (de-pression, anxiety, and somatization) seems war-ranted. Audiologic testing has only occasional diagnostic value, primarily in the patient with suspected Meniere’s disease or the rare case of acoustic neuroma. For both causes, one or more cochlear symptoms (hearing loss, ear full-ness, tinnitus) in addition to vertigo are typi-cally prominent. The one study evaluating ambulatory cardiac monitoring in dizzy pa-tients reported a low yield23; given the infre-quency of cardiac arrhythmias as a cause of dizziness, Holter or event monitoring should probably be limited to the occasional dizzy patient who either has had true syncope or, possibly, recurrent and unexplained presynco-pal episodes. Likewise, neuroimaging, brain stem evoked responses, and noninvasive vascu-lar testing are best reserved for the small subset of patients whose history, physical examination, or vestibular testing results suggest the possibil-ity of a central cause. Table 4 outlines a strategy for evaluating the dizzy patient in primary care, based on this paper and several previous re-views.38-40

While our literature review provides esti-mates of the frequency of various causes, it also highlights the limitations of available evi-dence. Use of a standard protocol for a pros-pective investigation of a large inception co-hort of dizzy patients, determination of cause by a panel, and clinical follow-up would better clarify the optimal evaluation of the dizzy patient.

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approach to the dizzy patient. J Clin Outcomes Manage1997;

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patient. Primary Care Rev1999; 2:3-11

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Kroenke et al?CAUSES OF DIZZINESS167

168

February 2000?SOUTHERN MEDICAL JOURNAL ?Vol. 93, No. 2

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英语阅读系列·有趣的字母

A biscuit can be a bear. 一块饼干可以是小熊。 A biscuit can be a butterfly. 一块饼干可以是蝴蝶。 But…If birds are nearby…但是…..如果小鸟恰好在旁边的话…… The biscuits can only be birds.饼干就只是小鸟啦。 Lesson 3 Cool Cat 酷猫卡里 Cary is a cool cat. 卡里是只酷酷的小猫。 Cary can cut carrots like this. 卡里能像这样切胡萝卜。 Cary can climb a coconut tree like this. 卡里能像这样爬树。 Cary can clean a crocodile like this. 卡里能像这样清理鳄鱼。 Cary can catch flies like this. 卡里能像这样抓苍蝇。 Can Cary color like this? 卡里能像这样涂色吗？ Yes! Cary is a cool cat. 是的！卡里是只酷酷的小猫。 Lesson 4 Dancing Dad 爸爸爱跳舞

一年级攀登英语一级A教学计划

一年级攀登英语一级A教学计划一年级攀登英语一级A教学计划 1、激发学生学习英语的兴趣,培养他们学习英语的积极态度,使他们初步建立学习英语的自信心。 2、培养学生具有一定的语感和良好的语音、语调及书写基础,以及良好的学习习惯。 3、培养学生的观察、记忆、思维、想象和创造能力。一年级攀登英语一级A教学计划 (20**学年度第一学期) 本学期我担任一年级4个班的攀登英语教学工作,现我对本学期教学工作做如下计划: 一、学生情况分析一年级的孩子的年龄多为6周岁,具有好奇、好活动、爱表现、善模仿等特点。他们的学习兴趣很浓,接受能力、模仿能力很强,学习习惯初步养成,因此在本学期应注重培养学生良好的学习习惯,训练学生的听说能力,调动他们的自主能动性、积极性,营造互帮互助,共同学习英语的语境。二、教学目标 1、激发学生学习英语的兴趣,培养他们学习英语的积极态度,使他们初步建立学习英语的自信心。 2、培养学生具有一定的语感和良好的语音、语调及书写基础,以及良好的学习习惯。

3、培养学生的观察、记忆、思维、想象和创造能力能在图片、手势、情境等非语言提示的帮助下,听懂清晰的话语和录音。三、教材分析本书共由五部分构成:本册教材学习内容包括:日常英语(Everyday English)、歌曲童谣(Songs and Chants).动画英语(Cartoon English)等 1、日常英语:与学生日常生活密切相关的情景对话,共12个话题,每个话题包括2-4句情景对话。 2、动画英语:以《迪士尼神奇英语》(上)VCD为基本学习材料。共6张VCD,12课,每课4个小节,由学生熟悉和喜欢的迪士尼动画片片段组合而成。 3、歌曲童谣:包括歌曲和童谣两大块,其中有精心制作的传统英文经典歌曲,也有攀登英语独创的童谣日常英语替换内容:以日常英语重点句型为主线,结合歌曲童谣和动画英语中高频出现的词汇进行的开放性交替。 5、节奏英语:将日常英语替换内容编成12段朗朗上口的韵文,并配以节奏明快的背景音乐形成的独特学习内容。四、教学措施 1、考虑到小学生好动爱玩的特点,以活动为课堂教学的主要形式,设计丰富多彩的教学活动,让学生在乐中学、学中用,从而保证学生英语学习的可持续性发展。 2、通过听、说、读、写、唱、游、演、画、做等形式,进行大量的语言操练和练习。

英语阅读系列·有趣的字母

攀登英语阅读系列·有趣的字母北京师范大学“认知神经科学与学习”国家重点实验室攀登英语项目组编著 Lesson1Frank the Rat 大老鼠弗兰克 Frank the rat is in a bag. 大老鼠弗兰克在袋子里呢。 Frank is in a hat. 他在圆顶帽子里呢。 Frank is in a pan. 他在平底锅里呢。 Frank is on an apple. 他在苹果上呢。 Frank is on a bat. 他在球棒上呢。 “Oh, no!” Frank is on a cat. “噢，糟了！”弗兰克落在了猫身上！ Lesson 2 The Biscuits 我们来做饼干 “I’m hungry!”“我饿了！” A biscuit…一块饼干可以是...... A biscuit can be a bus.一块饼干可以是公共汽车。 A biscuit canbe a bike. 和一块饼干可以是自行车。 A biscuit can be a boat. 一块饼干可以是小船。 A biscuit can be a banana. 一块饼干可以是香蕉。 A biscuit can be a bear. 一块饼干可以是小熊。 A biscuit can be a butterfly. 一块饼干可以是蝴蝶。 But…If birds are nearby…但是…..如果小鸟恰好在旁边的话…… The biscuits can only be birds.饼干就只是小鸟啦。 Lesson 3 Cool Cat 酷猫卡里 Cary is a cool cat. 卡里是只酷酷的小猫。 Cary can cut carrots like this. 卡里能像这样切胡萝卜。 Cary can climb a coconut tree like this. 卡里能像这样爬树。 Cary can clean a crocodile like this. 卡里能像这样清理鳄鱼。 Cary can catch flies like this.卡里能像这样抓苍蝇。 Can Cary color like this? 卡里能像这样涂色吗？ Yes! Cary is a cool cat. 是的！卡里是只酷酷的小猫。 Lesson 4 Dancing Dad 爸爸爱跳舞 Dad loves dancing! 爸爸爱跳舞！ Dad is dancing with the desk. 他和桌子一起跳。 Dad is dancing with the duck. 他和鸭子一起跳。 Dad is dancing with the door. 他和门一起跳。 Dad is dancing with the dog. 他和小狗一起跳。 Dad is dancing with the deer. 他和小鹿一起跳。 Where is Dad? 爸爸在哪儿呀？ Wow！哇！ What a dancing Dad! 真是个爱跳舞的爸爸！ Lesson 5 Red Ben 小本的红色世界 Ben likes red. 小本喜欢红色。 Ben paints the eggs red. 他把鸡蛋涂成红色。 Ben paints the eggplants red. 他把茄子涂成红色。 Ben paints the lemons red. 他把柠檬涂成红色。

(完整版)攀登英语-有趣的字母(中英文_纯文字_26篇全)

攀登英语——有趣的字母 A: Frank the rat 老鼠弗兰克 Frank the rat is in a bag. 大老鼠弗兰克在袋子里。 Frank is in a hat. 弗兰克在圆顶帽子里。 Frank is in a pan. 弗兰克在平底锅里。 Frank is on an apple. 弗兰克在苹果里。 Frank is on a bat. 弗兰克在球棒上。 “Oh/no!”F r ank is on a cat. “哦?不！”弗兰克落在了猫身上。 B：The Biscuits 饼干 “I’m h ungry!”“我饿了!” A biscuit, —块饼干 A biscuit can be a bus. —块饼干可以是公共汽车。 A biscuit can be a bike. 可以是自行车。 A biscuit can be a boat. 可以是船。 A biscuit can be a banana. 可以是香蕉。 A biscuit can be a bear.可以是小熊。 A biscuit can be a butterfly.可以是蝴蝶。 But，if birds are nearby,但是，如果鸟儿靠近 The biscuits can only be birds.饼干只能是小鸟啦。 C： Cool Cat酷猫卡里 Cary is a cool cat.卡里是只酷酷的小猫。 Cary can cut carrots like this.卡里能像这样切胡萝卜。 Cary can climb a coconut tree like this. 卡里能像这样爬树。Cary can clean a crocodile like this.卡里能像这样淸洁鳄鱼。Cary can catch flies like this.卡里能像这样抓苍蝇。 Can Cary color like this? 卡里能像这样涂色吗？ Yes!是的 Cary is a cool cat.卡里是只酷酷的小猫。 D: Dancing Dad爸爸爱跳舞 Dad loves dancing!爸爸爱跳舞！ Dad is dancing with the desk.他和桌子一起跳。

攀登英语-有趣的字母(中英文_纯文字_26篇全)教案资料

攀登英语-有趣的字母(中英文_纯文字_26 篇全)

英语阅读系列·有趣的字母

英语阅读系列·有趣的字母攀登英语阅读系列?有趣的字母攀登英语阅读系列·有趣的字母北京师范大学“认知神经科学与学习”国家重点实验室攀登英语项目组编著 Lesson1 Frank the Rat 大老鼠弗兰克 Frank the rat is in a bag. 大老鼠弗兰克在袋子里呢。

Frank is in a hat. 他在圆顶帽子里呢。Frank is in a pan. 他在平底锅里呢。Frank is on an apple. 他在苹果上呢。Frank is on a bat. 他在球棒上呢。“Oh, no!” Frank is on a cat. “噢，糟了！”弗兰克落在了猫身上！ Lesson 2 The Biscuits 我们来做饼干 “I'm hungry!”“我饿了！” A biscuit…一块饼干可以是...... A biscuit can be a bus. 一块饼干可以是公共汽车。 A biscuit can be a bike. 和一块饼干可以是自行车。 A biscuit can be a boat. 一块饼干可以是小船。 A biscuit can be a banana. 一块饼干可以是香蕉。．攀登英语阅读系列?有趣的字母 A biscuit can be a bear. 一块饼干可以是小熊。 A biscuit can be a butterfly. 一

块饼干可以是蝴蝶。 But…If birds are nearby…但是…..如果小鸟恰好在旁边的话…… The biscuits can only be birds.饼干就只是小鸟啦。 Lesson 3 Cool Cat 酷猫卡里 Cary is a cool cat. 卡里是只酷酷的小猫。 Cary can cut carrots like this. 卡里能像这样切胡萝卜。 Cary can climb a coconut tree like this. 卡里能像这样爬树。 Cary can clean a crocodile like this. 卡里能像这样清理鳄鱼。 Cary can catch flies like this. 卡里能像这样抓苍蝇。 Can Cary color like this? 卡里能像这样涂色吗？ Yes! Cary is a cool cat. 是的！卡里是只酷酷的小猫。爸爸爱跳舞Dancing Dad Lesson 4 攀登英语阅读系列?有趣的字母

攀登英语-有趣的字母(中英文_纯文字_26篇全)

攀登英语——有趣的字母 A:Franktherat老鼠弗兰克 Franktheratisinabag.大老鼠弗兰克在袋子里。Frankisinahat.弗兰克在圆顶帽子里。 Frankisinapan.弗兰克在平底锅里。 Frankisonanapple.弗兰克在苹果里。 Frankisonabat.弗兰克在球棒上。 “Oh/no!”F rankisonacat.“哦?不！”弗兰克落在了猫身上。 B：TheBiscuits饼干 “I’mhungry!”“我饿了!” Abiscuit,—块饼干 Abiscuitcanbeabus.—块饼干可以是公共汽车。Abiscuitcanbeabike.可以是自行车。 Abiscuitcanbeaboat.可以是船。 Abiscuitcanbeabanana.可以是香蕉。 Abiscuitcanbeabear.可以是小熊。Abiscuitcanbeabutterfly.可以是蝴蝶。 But，ifbirdsarenearby,但是，如果鸟儿靠近Thebiscuitscanonlybebirds.饼干只能是小鸟啦。 C：CoolCat酷猫卡里 Caryisacoolcat.卡里是只酷酷的小猫。Carycancutcarrotslikethis.卡里能像这样切胡萝卜。Carycanclimbacoconuttreelikethis.卡里能像这样爬树。Carycancleanacrocodilelikethis.卡里能像这样淸洁鳄鱼。Carycancatchflieslikethis.卡里能像这样抓苍蝇。CanCarycolorlikethis?卡里能像这样涂色吗？ Yes!是的 Caryisacoolcat.卡里是只酷酷的小猫。 D:DancingDad爸爸爱跳舞 Dadlovesdancing!爸爸爱跳舞！Dadisdancingwiththedesk.他和桌子一起跳。